diff --git a/mod/assign/mod_form.php b/mod/assign/mod_form.php
index d936422c4cc..86b04e24d8f 100644
--- a/mod/assign/mod_form.php
+++ b/mod/assign/mod_form.php
@@ -319,10 +319,13 @@ class mod_assign_mod_form extends moodleform_mod {
     public function add_completion_rules() {
         $mform =& $this->_form;
 
-        $mform->addElement('advcheckbox', 'completionsubmit', '', get_string('completionsubmit', 'assign'));
+        $suffix = $this->get_suffix();
+        $completionsubmitel = 'completionsubmit' . $suffix;
+        $mform->addElement('advcheckbox', $completionsubmitel, '', get_string('completionsubmit', 'assign'));
         // Enable this completion rule by default.
-        $mform->setDefault('completionsubmit', 1);
-        return array('completionsubmit');
+        $mform->setDefault($completionsubmitel, 1);
+
+        return [$completionsubmitel];
     }
 
     /**
@@ -332,7 +335,8 @@ class mod_assign_mod_form extends moodleform_mod {
      * @return bool
      */
     public function completion_rule_enabled($data) {
-        return !empty($data['completionsubmit']);
+        $suffix = $this->get_suffix();
+        return !empty($data['completionsubmit' . $suffix]);
     }
 
 }
diff --git a/mod/bigbluebuttonbn/mod_form.php b/mod/bigbluebuttonbn/mod_form.php
index 31bd487d752..96884691f80 100644
--- a/mod/bigbluebuttonbn/mod_form.php
+++ b/mod/bigbluebuttonbn/mod_form.php
@@ -143,10 +143,14 @@ class mod_bigbluebuttonbn_mod_form extends moodleform_mod {
     public function data_preprocessing(&$defaultvalues) {
         parent::data_preprocessing($defaultvalues);
 
+        $suffix = $this->get_suffix();
+        $completionattendanceenabledel = 'completionattendanceenabled' . $suffix;
+        $completionattendanceel = 'completionattendance' . $suffix;
+
         // Completion: tick by default if completion attendance settings is set to 1 or more.
-        $defaultvalues['completionattendanceenabled'] = 0;
-        if (!empty($defaultvalues['completionattendance'])) {
-            $defaultvalues['completionattendanceenabled'] = 1;
+        $defaultvalues[$completionattendanceenabledel] = 0;
+        if (!empty($defaultvalues[$completionattendanceel])) {
+            $defaultvalues[$completionattendanceenabledel] = 1;
         }
         // Check if we are Editing an existing instance.
         if ($this->current->instance) {
@@ -162,9 +166,9 @@ class mod_bigbluebuttonbn_mod_form extends moodleform_mod {
                 return;
             }
             // Completion: tick if completion attendance settings is set to 1 or more.
-            $defaultvalues['completionattendanceenabled'] = 0;
-            if (!empty($this->current->completionattendance)) {
-                $defaultvalues['completionattendanceenabled'] = 1;
+            $defaultvalues[$completionattendanceenabledel] = 0;
+            if (!empty($this->current->{$completionattendanceel})) {
+                $defaultvalues[$completionattendanceenabledel] = 1;
             }
         }
     }
@@ -204,19 +208,26 @@ class mod_bigbluebuttonbn_mod_form extends moodleform_mod {
             return [];
         }
 
+        $suffix = $this->get_suffix();
+
         // Elements for completion by Attendance.
         $attendance['grouplabel'] = get_string('completionattendancegroup', 'bigbluebuttonbn');
         $attendance['rulelabel'] = get_string('completionattendance', 'bigbluebuttonbn');
+        $completionattendanceenabledel = 'completionattendanceenabled' . $suffix;
+        $completionattendanceel = 'completionattendance' . $suffix;
+        $completionattendanceunitel = 'completionattendanceunit' . $suffix;
         $attendance['group'] = [
-            $mform->createElement('advcheckbox', 'completionattendanceenabled', '', $attendance['rulelabel'] . ' '),
-            $mform->createElement('text', 'completionattendance', '', ['size' => 3]),
-            $mform->createElement('static', 'completionattendanceunit', ' ', get_string('minutes', 'bigbluebuttonbn'))
+            $mform->createElement('advcheckbox', $completionattendanceenabledel, '', $attendance['rulelabel'] . ' '),
+            $mform->createElement('text', $completionattendanceel, '', ['size' => 3]),
+            $mform->createElement('static', $completionattendanceunitel, ' ', get_string('minutes', 'bigbluebuttonbn'))
         ];
-        $mform->setType('completionattendance', PARAM_INT);
-        $mform->addGroup($attendance['group'], 'completionattendancegroup', $attendance['grouplabel'], [' '], false);
-        $mform->addHelpButton('completionattendancegroup', 'completionattendancegroup', 'bigbluebuttonbn');
-        $mform->disabledIf('completionattendancegroup', 'completion', 'neq', COMPLETION_AGGREGATION_ANY);
-        $mform->disabledIf('completionattendance', 'completionattendanceenabled', 'notchecked');
+        $mform->setType($completionattendanceel, PARAM_INT);
+        $completionattendancegroupel = 'completionattendancegroup' . $suffix;
+        $mform->addGroup($attendance['group'], $completionattendancegroupel, $attendance['grouplabel'], ' ', false);
+        $mform->addHelpButton($completionattendancegroupel, 'completionattendancegroup', 'bigbluebuttonbn');
+        $completionel = 'completion' . $suffix;
+        $mform->disabledIf($completionattendancegroupel, $completionel, 'neq', COMPLETION_AGGREGATION_ANY);
+        $mform->disabledIf($completionattendanceel, $completionattendanceenabledel, 'notchecked');
 
         // Elements for completion by Engagement.
         $engagement['grouplabel'] = get_string('completionengagementgroup', 'bigbluebuttonbn');
@@ -225,23 +236,30 @@ class mod_bigbluebuttonbn_mod_form extends moodleform_mod {
         $engagement['raisehand'] = get_string('completionengagementraisehand', 'bigbluebuttonbn');
         $engagement['pollvotes'] = get_string('completionengagementpollvotes', 'bigbluebuttonbn');
         $engagement['emojis'] = get_string('completionengagementemojis', 'bigbluebuttonbn');
+
+        $completionengagementchatsel = 'completionengagementchats' . $suffix;
+        $completionengagementtalksel = 'completionengagementtalks' . $suffix;
+        $completionengagementraisehandel = 'completionengagementraisehand' . $suffix;
+        $completionengagementpollvotesel = 'completionengagementpollvotes' . $suffix;
+        $completionengagementemojisel = 'completionengagementemojis' . $suffix;
         $engagement['group'] = [
-            $mform->createElement('advcheckbox', 'completionengagementchats', '', $engagement['chatlabel'] . '  '),
-            $mform->createElement('advcheckbox', 'completionengagementtalks', '', $engagement['talklabel'] . '  '),
-            $mform->createElement('advcheckbox', 'completionengagementraisehand', '', $engagement['raisehand'] . '  '),
-            $mform->createElement('advcheckbox', 'completionengagementpollvotes', '', $engagement['pollvotes'] . '  '),
-            $mform->createElement('advcheckbox', 'completionengagementemojis', '', $engagement['emojis'] . '  '),
+            $mform->createElement('advcheckbox', $completionengagementchatsel, '', $engagement['chatlabel'] . '  '),
+            $mform->createElement('advcheckbox', $completionengagementtalksel, '', $engagement['talklabel'] . '  '),
+            $mform->createElement('advcheckbox', $completionengagementraisehandel, '', $engagement['raisehand'] . '  '),
+            $mform->createElement('advcheckbox', $completionengagementpollvotesel, '', $engagement['pollvotes'] . '  '),
+            $mform->createElement('advcheckbox', $completionengagementemojisel, '', $engagement['emojis'] . '  '),
         ];
-        $mform->addGroup($engagement['group'], 'completionengagementgroup', $engagement['grouplabel'], [' '], false);
-        $mform->addGroupRule('completionattendancegroup', [
-            'completionattendance' => [
+        $completionengagementgroupel = 'completionengagementgroup' . $suffix;
+        $mform->addGroup($engagement['group'], $completionengagementgroupel, $engagement['grouplabel'], ' ', false);
+        $mform->addGroupRule($completionattendancegroupel, [
+            $completionattendanceel => [
                 [null, 'numeric', null, 'client']
             ]
         ]);
-        $mform->addHelpButton('completionengagementgroup', 'completionengagementgroup', 'bigbluebuttonbn');
-        $mform->disabledIf('completionengagementgroup', 'completion', 'neq', COMPLETION_AGGREGATION_ANY);
+        $mform->addHelpButton($completionengagementgroupel, 'completionengagementgroup', 'bigbluebuttonbn');
+        $mform->disabledIf($completionengagementgroupel, $completionel, 'neq', COMPLETION_AGGREGATION_ANY);
 
-        return ['completionattendancegroup', 'completionengagementgroup'];
+        return [$completionattendancegroupel, $completionengagementgroupel];
     }
 
     /**
@@ -251,12 +269,13 @@ class mod_bigbluebuttonbn_mod_form extends moodleform_mod {
      * @return bool True if one or more rules is enabled, false if none are.
      */
     public function completion_rule_enabled($data) {
-        return (!empty($data['completionattendanceenabled']) && $data['completionattendance'] != 0)
-            || !empty($data['completionengagementchats'])
-            || !empty($data['completionengagementtalks'])
-            || !empty($data['completionengagementraisehand'])
-            || !empty($data['completionengagementpollvotes'])
-            || !empty($data['completionengagementemojis']);
+        $suffix = $this->get_suffix();
+        return (!empty($data['completionattendanceenabled' . $suffix]) && $data['completionattendance' . $suffix] != 0)
+            || !empty($data['completionengagementchats' . $suffix])
+            || !empty($data['completionengagementtalks' . $suffix])
+            || !empty($data['completionengagementraisehand' . $suffix])
+            || !empty($data['completionengagementpollvotes' . $suffix])
+            || !empty($data['completionengagementemojis' . $suffix]);
     }
 
     /**
@@ -271,9 +290,11 @@ class mod_bigbluebuttonbn_mod_form extends moodleform_mod {
         parent::data_postprocessing($data);
         // Turn off completion settings if the checkboxes aren't ticked.
         if (!empty($data->completionunlocked)) {
-            $autocompletion = !empty($data->completion) && $data->completion == COMPLETION_TRACKING_AUTOMATIC;
-            if (empty($data->completionattendanceenabled) || !$autocompletion) {
-                $data->completionattendance = 0;
+            $suffix = $this->get_suffix();
+            $completion = $data->{'completion' . $suffix};
+            $autocompletion = !empty($completion) && $completion == COMPLETION_TRACKING_AUTOMATIC;
+            if (empty($data->{'completionattendanceenabled' . $suffix}) || !$autocompletion) {
+                $data->{'completionattendance' . $suffix} = 0;
             }
         }
     }
@@ -703,7 +724,10 @@ class mod_bigbluebuttonbn_mod_form extends moodleform_mod {
         $completion = new completion_info($COURSE);
         if ($completion->is_enabled()) {
             $mform = $this->_form;
-            foreach (['completionattendancegroup', 'completionengagementgroup'] as $groupname) {
+            $suffix = $this->get_suffix();
+            $completionattendancegroupel = 'completionattendancegroup' . $suffix;
+            $completionengagementgroupel = 'completionengagementgroup' . $suffix;
+            foreach ([$completionattendancegroupel, $completionengagementgroupel] as $groupname) {
                 if ($mform->elementExists($groupname)) {
                     $element = $mform->getElement($groupname);
                     if ($element->isFrozen()) {
diff --git a/mod/choice/mod_form.php b/mod/choice/mod_form.php
index 47a400bf8df..7acc4f76246 100644
--- a/mod/choice/mod_form.php
+++ b/mod/choice/mod_form.php
@@ -138,10 +138,11 @@ class mod_choice_mod_form extends moodleform_mod {
      */
     public function data_postprocessing($data) {
         parent::data_postprocessing($data);
-        // Set up completion section even if checkbox is not ticked
+        // Set up completion section even if checkbox is not ticked.
         if (!empty($data->completionunlocked)) {
-            if (empty($data->completionsubmit)) {
-                $data->completionsubmit = 0;
+            $suffix = $this->get_suffix();
+            if (empty($data->{'completionsubmit' . $suffix})) {
+                $data->{'completionsubmit' . $suffix} = 0;
             }
         }
     }
@@ -165,17 +166,19 @@ class mod_choice_mod_form extends moodleform_mod {
         return $errors;
     }
 
-    function add_completion_rules() {
+    public function add_completion_rules() {
         $mform =& $this->_form;
 
-        $mform->addElement('checkbox', 'completionsubmit', '', get_string('completionsubmit', 'choice'));
+        $suffix = $this->get_suffix();
+        $completionsubmitel = 'completionsubmit' . $suffix;
+        $mform->addElement('checkbox', $completionsubmitel, '', get_string('completionsubmit', 'choice'));
         // Enable this completion rule by default.
-        $mform->setDefault('completionsubmit', 1);
-        return array('completionsubmit');
+        $mform->setDefault($completionsubmitel, 1);
+        return [$completionsubmitel];
     }
 
-    function completion_rule_enabled($data) {
-        return !empty($data['completionsubmit']);
+    public function completion_rule_enabled($data) {
+        $suffix = $this->get_suffix();
+        return !empty($data['completionsubmit' . $suffix]);
     }
 }
-
diff --git a/mod/data/mod_form.php b/mod/data/mod_form.php
index c75bb1bd3b3..6b535f88a5a 100644
--- a/mod/data/mod_form.php
+++ b/mod/data/mod_form.php
@@ -123,19 +123,37 @@ class mod_data_mod_form extends moodleform_mod {
      */
     public function add_completion_rules() {
         $mform = & $this->_form;
-        $group = array();
-        $group[] = $mform->createElement('checkbox', 'completionentriesenabled', '',
-                get_string('completionentriescount', 'data'));
-        $group[] = $mform->createElement('text', 'completionentries',
-                get_string('completionentriescount', 'data'), array('size' => '1'));
+        $group = [];
 
-        $mform->addGroup($group, 'completionentriesgroup', get_string('completionentries', 'data'),
-                array(' '), false);
-        $mform->disabledIf('completionentries', 'completionentriesenabled', 'notchecked');
-        $mform->setDefault('completionentries', 1);
-        $mform->setType('completionentries', PARAM_INT);
+        $suffix = $this->get_suffix();
+        $completionentriesenabledel = 'completionentriesenabled' . $suffix;
+        $group[] = $mform->createElement(
+            'checkbox',
+            $completionentriesenabledel,
+            '',
+            get_string('completionentriescount', 'data')
+        );
+        $completionentriesel = 'completionentries' . $suffix;
+        $group[] = $mform->createElement(
+            'text',
+            $completionentriesel,
+            get_string('completionentriescount', 'data'),
+            ['size' => '1']
+        );
+
+        $completionentriesgroupel = 'completionentriesgroup' . $suffix;
+        $mform->addGroup(
+            $group,
+            $completionentriesgroupel,
+            get_string('completionentries', 'data'),
+            [' '],
+            false
+        );
+        $mform->disabledIf($completionentriesel, $completionentriesenabledel, 'notchecked');
+        $mform->setDefault($completionentriesel, 1);
+        $mform->setType($completionentriesel, PARAM_INT);
         /* This ensures the elements are disabled unless completion rules are enabled */
-        return array('completionentriesgroup');
+        return [$completionentriesgroupel];
     }
 
     /**
@@ -145,7 +163,8 @@ class mod_data_mod_form extends moodleform_mod {
      * @return bool True if one or more rules is enabled, false if none are.
      */
     public function completion_rule_enabled($data) {
-        return (!empty($data['completionentriesenabled']) && $data['completionentries'] != 0);
+        $suffix = $this->get_suffix();
+        return (!empty($data['completionentriesenabled' . $suffix]) && $data['completionentries' . $suffix] != 0);
     }
 
       /**
@@ -156,9 +175,13 @@ class mod_data_mod_form extends moodleform_mod {
        */
     public function data_preprocessing(&$defaultvalues) {
         parent::data_preprocessing($defaultvalues);
-        $defaultvalues['completionentriesenabled'] = !empty($defaultvalues['completionentries']) ? 1 : 0;
-        if (empty($defaultvalues['completionentries'])) {
-            $defaultvalues['completionentries'] = 1;
+
+        $suffix = $this->get_suffix();
+        $completionentriesenabledel = 'completionentriesenabled' . $suffix;
+        $completionentriesel = 'completionentries' . $suffix;
+        $defaultvalues[$completionentriesenabledel] = !empty($defaultvalues[$completionentriesel]) ? 1 : 0;
+        if (empty($defaultvalues[$completionentriesel])) {
+            $defaultvalues[$completionentriesel] = 1;
         }
     }
 
@@ -173,9 +196,13 @@ class mod_data_mod_form extends moodleform_mod {
     public function data_postprocessing($data) {
         parent::data_postprocessing($data);
         if (!empty($data->completionunlocked)) {
-            $autocompletion = !empty($data->completion) && $data->completion == COMPLETION_TRACKING_AUTOMATIC;
-            if (empty($data->completionentriesenabled) || !$autocompletion) {
-                $data->completionentries = 0;
+            $suffix = $this->get_suffix();
+            $completionel = 'completion' . $suffix;
+            $completionentriesenabledel = 'completionentriesenabled' . $suffix;
+            $autocompletion = !empty($data->{$completionel}) && $data->{$completionel} == COMPLETION_TRACKING_AUTOMATIC;
+            if (empty($data->{$completionentriesenabledel}) || !$autocompletion) {
+                $completionentriesel = 'completionentries' . $suffix;
+                $data->{$completionentriesel} = 0;
             }
         }
     }
diff --git a/mod/feedback/mod_form.php b/mod/feedback/mod_form.php
index 627690f41fc..84fdfb70445 100644
--- a/mod/feedback/mod_form.php
+++ b/mod/feedback/mod_form.php
@@ -175,11 +175,12 @@ class mod_feedback_mod_form extends moodleform_mod {
             $data->page_after_submit = $data->page_after_submit_editor['text'];
 
             if (!empty($data->completionunlocked)) {
-                // Turn off completion settings if the checkboxes aren't ticked
-                $autocompletion = !empty($data->completion) &&
-                    $data->completion == COMPLETION_TRACKING_AUTOMATIC;
-                if (!$autocompletion || empty($data->completionsubmit)) {
-                    $data->completionsubmit=0;
+                // Turn off completion settings if the checkboxes aren't ticked.
+                $suffix = $this->get_suffix();
+                $completion = $data->{'completion' . $suffix};
+                $autocompletion = !empty($completion) && $completion == COMPLETION_TRACKING_AUTOMATIC;
+                if (!$autocompletion || empty($data->{'completionsubmit' . $suffix})) {
+                    $data->{'completionsubmit' . $suffix} = 0;
                 }
             }
         }
@@ -206,16 +207,20 @@ class mod_feedback_mod_form extends moodleform_mod {
     public function add_completion_rules() {
         $mform =& $this->_form;
 
+        $suffix = $this->get_suffix();
+        $completionsubmitel = 'completionsubmit' . $suffix;
         $mform->addElement('checkbox',
-                           'completionsubmit',
-                           '',
-                           get_string('completionsubmit', 'feedback'));
+            $completionsubmitel,
+            '',
+            get_string('completionsubmit', 'feedback')
+        );
         // Enable this completion rule by default.
-        $mform->setDefault('completionsubmit', 1);
-        return array('completionsubmit');
+        $mform->setDefault($completionsubmitel, 1);
+        return [$completionsubmitel];
     }
 
     public function completion_rule_enabled($data) {
-        return !empty($data['completionsubmit']);
+        $suffix = $this->get_suffix();
+        return !empty($data['completionsubmit' . $suffix]);
     }
 }
diff --git a/mod/forum/mod_form.php b/mod/forum/mod_form.php
index d1b194e2980..7b9a45d8610 100644
--- a/mod/forum/mod_form.php
+++ b/mod/forum/mod_form.php
@@ -405,30 +405,36 @@ class mod_forum_mod_form extends moodleform_mod {
         }
     }
 
-    function data_preprocessing(&$default_values) {
-        parent::data_preprocessing($default_values);
+    public function data_preprocessing(&$defaultvalues) {
+        parent::data_preprocessing($defaultvalues);
+
+        $suffix = $this->get_suffix();
+        $completiondiscussionsenabledel = 'completiondiscussionsenabled' . $suffix;
+        $completiondiscussionsel = 'completiondiscussions' . $suffix;
+        $completionrepliesenabledel = 'completionrepliesenabled' . $suffix;
+        $completionrepliesel = 'completionreplies' . $suffix;
+        $completionpostsel = 'completionposts' . $suffix;
+        $completionpostsenabledel = 'completionpostsenabled' . $suffix;
 
         // Set up the completion checkboxes which aren't part of standard data.
         // We also make the default value (if you turn on the checkbox) for those
         // numbers to be 1, this will not apply unless checkbox is ticked.
-        $default_values['completiondiscussionsenabled']=
-            !empty($default_values['completiondiscussions']) ? 1 : 0;
-        if (empty($default_values['completiondiscussions'])) {
-            $default_values['completiondiscussions']=1;
+        $defaultvalues[$completiondiscussionsenabledel] = !empty($defaultvalues[$completiondiscussionsel]) ? 1 : 0;
+        if (empty($defaultvalues[$completiondiscussionsel])) {
+            $defaultvalues[$completiondiscussionsel] = 1;
         }
-        $default_values['completionrepliesenabled']=
-            !empty($default_values['completionreplies']) ? 1 : 0;
-        if (empty($default_values['completionreplies'])) {
-            $default_values['completionreplies']=1;
+        $defaultvalues[$completionrepliesenabledel] = !empty($defaultvalues[$completionrepliesel]) ? 1 : 0;
+        if (empty($defaultvalues[$completionrepliesel])) {
+            $defaultvalues[$completionrepliesel] = 1;
         }
         // Tick by default if Add mode or if completion posts settings is set to 1 or more.
-        if (empty($this->_instance) || !empty($default_values['completionposts'])) {
-            $default_values['completionpostsenabled'] = 1;
+        if (empty($this->_instance) || !empty($defaultvalues[$completionpostsel])) {
+            $defaultvalues[$completionpostsenabledel] = 1;
         } else {
-            $default_values['completionpostsenabled'] = 0;
+            $defaultvalues[$completionpostsenabledel] = 0;
         }
-        if (empty($default_values['completionposts'])) {
-            $default_values['completionposts']=1;
+        if (empty($defaultvalues[$completionpostsel])) {
+            $defaultvalues[$completionpostsel] = 1;
         }
     }
 
@@ -438,36 +444,54 @@ class mod_forum_mod_form extends moodleform_mod {
      * @return array Array of string IDs of added items, empty array if none
      */
     public function add_completion_rules() {
-        $mform =& $this->_form;
+        $mform = $this->_form;
 
-        $group=array();
-        $group[] =& $mform->createElement('checkbox', 'completionpostsenabled', '', get_string('completionposts','forum'));
-        $group[] =& $mform->createElement('text', 'completionposts', '', array('size'=>3));
-        $mform->setType('completionposts',PARAM_INT);
-        $mform->addGroup($group, 'completionpostsgroup', get_string('completionpostsgroup','forum'), array(' '), false);
-        $mform->disabledIf('completionposts','completionpostsenabled','notchecked');
+        $suffix = $this->get_suffix();
 
-        $group=array();
-        $group[] =& $mform->createElement('checkbox', 'completiondiscussionsenabled', '', get_string('completiondiscussions','forum'));
-        $group[] =& $mform->createElement('text', 'completiondiscussions', '', array('size'=>3));
-        $mform->setType('completiondiscussions',PARAM_INT);
-        $mform->addGroup($group, 'completiondiscussionsgroup', get_string('completiondiscussionsgroup','forum'), array(' '), false);
-        $mform->disabledIf('completiondiscussions','completiondiscussionsenabled','notchecked');
+        $group = [];
+        $completionpostsenabledel = 'completionpostsenabled' . $suffix;
+        $group[] =& $mform->createElement('checkbox', $completionpostsenabledel, '', get_string('completionposts', 'forum'));
+        $completionpostsel = 'completionposts' . $suffix;
+        $group[] =& $mform->createElement('text', $completionpostsel, '', ['size' => 3]);
+        $mform->setType($completionpostsel, PARAM_INT);
+        $completionpostsgroupel = 'completionpostsgroup' . $suffix;
+        $mform->addGroup($group, $completionpostsgroupel, get_string('completionpostsgroup', 'forum'), ' ', false);
+        $mform->disabledIf($completionpostsel, $completionpostsenabledel, 'notchecked');
 
-        $group=array();
-        $group[] =& $mform->createElement('checkbox', 'completionrepliesenabled', '', get_string('completionreplies','forum'));
-        $group[] =& $mform->createElement('text', 'completionreplies', '', array('size'=>3));
-        $mform->setType('completionreplies',PARAM_INT);
-        $mform->addGroup($group, 'completionrepliesgroup', get_string('completionrepliesgroup','forum'), array(' '), false);
-        $mform->disabledIf('completionreplies','completionrepliesenabled','notchecked');
+        $group = [];
+        $completiondiscussionsenabledel = 'completiondiscussionsenabled' . $suffix;
+        $group[] =& $mform->createElement(
+            'checkbox',
+            $completiondiscussionsenabledel,
+            '',
+            get_string('completiondiscussions',
+            'forum')
+        );
+        $completiondiscussionsel = 'completiondiscussions' . $suffix;
+        $group[] =& $mform->createElement('text', $completiondiscussionsel, '', ['size' => 3]);
+        $mform->setType($completiondiscussionsel, PARAM_INT);
+        $completiondiscussionsgroupel = 'completiondiscussionsgroup' . $suffix;
+        $mform->addGroup($group, $completiondiscussionsgroupel, get_string('completiondiscussionsgroup', 'forum'), ' ', false);
+        $mform->disabledIf($completiondiscussionsel, $completiondiscussionsenabledel, 'notchecked');
 
-        return array('completiondiscussionsgroup','completionrepliesgroup','completionpostsgroup');
+        $group = [];
+        $completionrepliesenabledel = 'completionrepliesenabled' . $suffix;
+        $group[] =& $mform->createElement('checkbox', $completionrepliesenabledel, '', get_string('completionreplies', 'forum'));
+        $completionrepliesel = 'completionreplies' . $suffix;
+        $group[] =& $mform->createElement('text', $completionrepliesel, '', ['size' => 3]);
+        $mform->setType($completionrepliesel, PARAM_INT);
+        $completionrepliesgroupel = 'completionrepliesgroup' . $suffix;
+        $mform->addGroup($group, $completionrepliesgroupel, get_string('completionrepliesgroup', 'forum'), ' ', false);
+        $mform->disabledIf($completionrepliesel, $completionrepliesenabledel, 'notchecked');
+
+        return [$completiondiscussionsgroupel, $completionrepliesgroupel, $completionpostsgroupel];
     }
 
-    function completion_rule_enabled($data) {
-        return (!empty($data['completiondiscussionsenabled']) && $data['completiondiscussions']!=0) ||
-            (!empty($data['completionrepliesenabled']) && $data['completionreplies']!=0) ||
-            (!empty($data['completionpostsenabled']) && $data['completionposts']!=0);
+    public function completion_rule_enabled($data) {
+        $suffix = $this->get_suffix();
+        return (!empty($data['completiondiscussionsenabled' . $suffix]) && $data['completiondiscussions' . $suffix] != 0) ||
+            (!empty($data['completionrepliesenabled' . $suffix]) && $data['completionreplies' . $suffix] != 0) ||
+            (!empty($data['completionpostsenabled' . $suffix]) && $data['completionposts' . $suffix] != 0);
     }
 
     /**
@@ -506,17 +530,19 @@ class mod_forum_mod_form extends moodleform_mod {
      */
     public function data_postprocessing($data) {
         parent::data_postprocessing($data);
-        // Turn off completion settings if the checkboxes aren't ticked
+        // Turn off completion settings if the checkboxes aren't ticked.
         if (!empty($data->completionunlocked)) {
-            $autocompletion = !empty($data->completion) && $data->completion==COMPLETION_TRACKING_AUTOMATIC;
-            if (empty($data->completiondiscussionsenabled) || !$autocompletion) {
-                $data->completiondiscussions = 0;
+            $suffix = $this->get_suffix();
+            $completion = $data->{'completion' . $suffix};
+            $autocompletion = !empty($completion) && $completion == COMPLETION_TRACKING_AUTOMATIC;
+            if (empty($data->{'completiondiscussionsenabled' . $suffix}) || !$autocompletion) {
+                $data->{'completiondiscussions' . $suffix} = 0;
             }
-            if (empty($data->completionrepliesenabled) || !$autocompletion) {
-                $data->completionreplies = 0;
+            if (empty($data->{'completionrepliesenabled' . $suffix}) || !$autocompletion) {
+                $data->{'completionreplies' . $suffix} = 0;
             }
-            if (empty($data->completionpostsenabled) || !$autocompletion) {
-                $data->completionposts = 0;
+            if (empty($data->{'completionpostsenabled' . $suffix}) || !$autocompletion) {
+                $data->{'completionposts' . $suffix} = 0;
             }
         }
     }
diff --git a/mod/glossary/mod_form.php b/mod/glossary/mod_form.php
index c2f65e14463..5c75fb13fdf 100644
--- a/mod/glossary/mod_form.php
+++ b/mod/glossary/mod_form.php
@@ -163,43 +163,57 @@ class mod_glossary_mod_form extends moodleform_mod {
         }
     }
 
-    function data_preprocessing(&$default_values){
-        parent::data_preprocessing($default_values);
+    public function data_preprocessing(&$defaultvalues) {
+        parent::data_preprocessing($defaultvalues);
 
         // Fallsback on the default setting if 'Entries shown per page' has been left blank.
         // This prevents the field from being required and expand its section which should not
         // be the case if there is a default value defined.
-        if (empty($default_values['entbypage']) || $default_values['entbypage'] < 0) {
-            $default_values['entbypage'] = $this->get_default_entbypage();
+        if (empty($defaultvalues['entbypage']) || $defaultvalues['entbypage'] < 0) {
+            $defaultvalues['entbypage'] = $this->get_default_entbypage();
         }
 
+        $suffix = $this->get_suffix();
+        $completionentriesel = 'completionentries' . $suffix;
+        $completionentriesenabledel = 'completionentriesenabled' . $suffix;
+
         // Set up the completion checkboxes which aren't part of standard data.
         // Tick by default if Add mode or if completion entries settings is set to 1 or more.
-        if (empty($this->_instance) || !empty($default_values['completionentries'])) {
-            $default_values['completionentriesenabled'] = 1;
+        if (empty($this->_instance) || !empty($defaultvalues[$completionentriesel])) {
+            $defaultvalues[$completionentriesenabledel] = 1;
         } else {
-            $default_values['completionentriesenabled'] = 0;
+            $defaultvalues[$completionentriesenabledel] = 0;
         }
-        if (empty($default_values['completionentries'])) {
-            $default_values['completionentries']=1;
+        if (empty($defaultvalues[$completionentriesel])) {
+            $defaultvalues[$completionentriesel] = 1;
         }
     }
 
-    function add_completion_rules() {
-        $mform =& $this->_form;
+    public function add_completion_rules() {
+        $mform = $this->_form;
+        $suffix = $this->get_suffix();
 
-        $group=array();
-        $group[] =& $mform->createElement('checkbox', 'completionentriesenabled', '', get_string('completionentries','glossary'));
-        $group[] =& $mform->createElement('text', 'completionentries', '', array('size'=>3));
-        $mform->setType('completionentries', PARAM_INT);
-        $mform->addGroup($group, 'completionentriesgroup', get_string('completionentriesgroup','glossary'), array(' '), false);
-        $mform->disabledIf('completionentries','completionentriesenabled','notchecked');
+        $group = [];
+        $completionentriesenabledel = 'completionentriesenabled' . $suffix;
+        $group[] =& $mform->createElement(
+            'checkbox',
+            $completionentriesenabledel,
+            '',
+            get_string('completionentries', 'glossary')
+        );
+        $completionentriesel = 'completionentries' . $suffix;
+        $group[] =& $mform->createElement('text', $completionentriesel, '', ['size' => 3]);
+        $mform->setType($completionentriesel, PARAM_INT);
+        $completionentriesgroupel = 'completionentriesgroup' . $suffix;
+        $mform->addGroup($group, $completionentriesgroupel, get_string('completionentriesgroup', 'glossary'), ' ', false);
+        $mform->disabledIf($completionentriesel, $completionentriesenabledel, 'notchecked');
 
-        return array('completionentriesgroup');
+        return [$completionentriesgroupel];
     }
 
-    function completion_rule_enabled($data) {
-        return (!empty($data['completionentriesenabled']) && $data['completionentries']!=0);
+    public function completion_rule_enabled($data) {
+        $suffix = $this->get_suffix();
+        return (!empty($data['completionentriesenabled' . $suffix]) && $data['completionentries' . $suffix] != 0);
     }
 
     /**
@@ -213,10 +227,12 @@ class mod_glossary_mod_form extends moodleform_mod {
     public function data_postprocessing($data) {
         parent::data_postprocessing($data);
         if (!empty($data->completionunlocked)) {
-            // Turn off completion settings if the checkboxes aren't ticked
-            $autocompletion = !empty($data->completion) && $data->completion==COMPLETION_TRACKING_AUTOMATIC;
-            if (empty($data->completionentriesenabled) || !$autocompletion) {
-                $data->completionentries = 0;
+            // Turn off completion settings if the checkboxes aren't ticked.
+            $suffix = $this->get_suffix();
+            $completion = $data->{'completion' . $suffix};
+            $autocompletion = !empty($completion) && $completion == COMPLETION_TRACKING_AUTOMATIC;
+            if (empty($data->{'completionentriesenabled' . $suffix}) || !$autocompletion) {
+                $data->{'completionentries' . $suffix} = 0;
             }
         }
     }
@@ -232,4 +248,3 @@ class mod_glossary_mod_form extends moodleform_mod {
     }
 
 }
-
diff --git a/mod/lesson/mod_form.php b/mod/lesson/mod_form.php
index be2cca26a53..88f87925047 100644
--- a/mod/lesson/mod_form.php
+++ b/mod/lesson/mod_form.php
@@ -365,8 +365,10 @@ class mod_lesson_mod_form extends moodleform_mod {
         }
 
         // Set up the completion checkbox which is not part of standard data.
-        $defaultvalues['completiontimespentenabled'] =
-            !empty($defaultvalues['completiontimespent']) ? 1 : 0;
+        $suffix = $this->get_suffix();
+        $completiontimespentenabledel = 'completiontimespentenabled' . $suffix;
+        $completiontimespentel = 'completiontimespent' . $suffix;
+        $defaultvalues[$completiontimespentenabledel] = !empty($defaultvalues[$completiontimespentel]) ? 1 : 0;
 
         if ($this->current->instance) {
             // Editing existing instance - copy existing files into draft area.
@@ -406,20 +408,32 @@ class mod_lesson_mod_form extends moodleform_mod {
     public function add_completion_rules() {
         $mform = $this->_form;
 
-        $mform->addElement('checkbox', 'completionendreached', get_string('completionendreached', 'lesson'),
-                get_string('completionendreached_desc', 'lesson'));
+        $suffix = $this->get_suffix();
+        $completionendreachedel = 'completionendreached' . $suffix;
+        $mform->addElement(
+            'checkbox', $completionendreachedel,
+            get_string('completionendreached', 'lesson'),
+            get_string('completionendreached_desc', 'lesson')
+        );
         // Enable this completion rule by default.
-        $mform->setDefault('completionendreached', 1);
+        $mform->setDefault($completionendreachedel, 1);
 
-        $group = array();
-        $group[] =& $mform->createElement('checkbox', 'completiontimespentenabled', '',
-                get_string('completiontimespent', 'lesson'));
-        $group[] =& $mform->createElement('duration', 'completiontimespent', '', array('optional' => false));
-        $mform->addGroup($group, 'completiontimespentgroup', get_string('completiontimespentgroup', 'lesson'), array(' '), false);
-        $mform->disabledIf('completiontimespent[number]', 'completiontimespentenabled', 'notchecked');
-        $mform->disabledIf('completiontimespent[timeunit]', 'completiontimespentenabled', 'notchecked');
+        $group = [];
+        $completiontimespentenabledel = 'completiontimespentenabled' . $suffix;
+        $group[] =& $mform->createElement(
+            'checkbox',
+            $completiontimespentenabledel,
+            '',
+            get_string('completiontimespent', 'lesson')
+        );
+        $completiontimespentel = 'completiontimespent' . $suffix;
+        $group[] =& $mform->createElement('duration', $completiontimespentel, '', ['optional' => false]);
+        $completiontimespentgroupel = 'completiontimespentgroup' . $suffix;
+        $mform->addGroup($group, $completiontimespentgroupel, get_string('completiontimespentgroup', 'lesson'), ' ', false);
+        $mform->disabledIf($completiontimespentel . '[number]', $completiontimespentenabledel, 'notchecked');
+        $mform->disabledIf($completiontimespentel . '[timeunit]', $completiontimespentenabledel, 'notchecked');
 
-        return array('completionendreached', 'completiontimespentgroup');
+        return [$completionendreachedel, $completiontimespentgroupel];
     }
 
     /**
@@ -429,7 +443,8 @@ class mod_lesson_mod_form extends moodleform_mod {
      * @return bool True if one or more rules is enabled, false if none are.
      */
     public function completion_rule_enabled($data) {
-        return !empty($data['completionendreached']) || $data['completiontimespent'] > 0;
+        $suffix = $this->get_suffix();
+        return !empty($data['completionendreached' . $suffix]) || $data['completiontimespent' . $suffix] > 0;
     }
 
     /**
@@ -444,14 +459,15 @@ class mod_lesson_mod_form extends moodleform_mod {
         parent::data_postprocessing($data);
         // Turn off completion setting if the checkbox is not ticked.
         if (!empty($data->completionunlocked)) {
-            $autocompletion = !empty($data->completion) && $data->completion == COMPLETION_TRACKING_AUTOMATIC;
-            if (empty($data->completiontimespentenabled) || !$autocompletion) {
-                $data->completiontimespent = 0;
+            $suffix = $this->get_suffix();
+            $completion = $data->{'completion' . $suffix};
+            $autocompletion = !empty($completion) && $completion == COMPLETION_TRACKING_AUTOMATIC;
+            if (empty($data->{'completiontimespentenabled' . $suffix}) || !$autocompletion) {
+                $data->{'completiontimespent' . $suffix} = 0;
             }
-            if (empty($data->completionendreached) || !$autocompletion) {
-                $data->completionendreached = 0;
+            if (empty($data->{'completionendreached' . $suffix}) || !$autocompletion) {
+                $data->{'completionendreached' . $suffix} = 0;
             }
         }
     }
 }
-
diff --git a/mod/quiz/mod_form.php b/mod/quiz/mod_form.php
index cf91026c424..b3c0cbf9e04 100644
--- a/mod/quiz/mod_form.php
+++ b/mod/quiz/mod_form.php
@@ -491,10 +491,13 @@ class mod_quiz_mod_form extends moodleform_mod {
             }
         }
 
-        if (empty($toform['completionminattempts'])) {
-            $toform['completionminattempts'] = 1;
+        $suffix = $this->get_suffix();
+        $completionminattemptsel = 'completionminattempts' . $suffix;
+        if (empty($toform[$completionminattemptsel])) {
+            $toform[$completionminattemptsel] = 1;
         } else {
-            $toform['completionminattemptsenabled'] = $toform['completionminattempts'] > 0;
+            $completionminattemptsenabledel = 'completionminattemptsenabled' . $suffix;
+            $toform[$completionminattemptsenabledel] = $toform[$completionminattemptsel] > 0;
         }
     }
 
@@ -510,9 +513,11 @@ class mod_quiz_mod_form extends moodleform_mod {
         parent::data_postprocessing($data);
         if (!empty($data->completionunlocked)) {
             // Turn off completion settings if the checkboxes aren't ticked.
-            $autocompletion = !empty($data->completion) && $data->completion == COMPLETION_TRACKING_AUTOMATIC;
-            if (empty($data->completionminattemptsenabled) || !$autocompletion) {
-                $data->completionminattempts = 0;
+            $suffix = $this->get_suffix();
+            $completion = $data->{'completion' . $suffix};
+            $autocompletion = !empty($completion) && $completion == COMPLETION_TRACKING_AUTOMATIC;
+            if (empty($data->{'completionminattemptsenabled' . $suffix}) || !$autocompletion) {
+                $data->{'completionminattempts' . $suffix} = 0;
             }
         }
     }
@@ -534,9 +539,12 @@ class mod_quiz_mod_form extends moodleform_mod {
             }
         }
 
-        if (!empty($data['completionminattempts'])) {
-            if ($data['attempts'] > 0 && $data['completionminattempts'] > $data['attempts']) {
-                $errors['completionminattemptsgroup'] = get_string('completionminattemptserror', 'quiz');
+        $suffix = $this->get_suffix();
+        $completionminattemptsel = 'completionminattempts' . $suffix;
+        if (!empty($data[$completionminattemptsel])) {
+            if ($data['attempts'] > 0 && $data[$completionminattemptsel] > $data['attempts']) {
+                $completionminattemptsgroupel = 'completionminattemptsgroup' . $suffix;
+                $errors[$completionminattemptsgroupel] = get_string('completionminattemptserror', 'quiz');
             }
         }
 
@@ -607,23 +615,36 @@ class mod_quiz_mod_form extends moodleform_mod {
      */
     public function add_completion_rules() {
         $mform = $this->_form;
+        $suffix = $this->get_suffix();
         $items = [];
 
-        $mform->addElement('advcheckbox', 'completionattemptsexhausted', null,
+        $completionattemptsexhaustedel = 'completionattemptsexhausted' . $suffix;
+        $mform->addElement(
+            'advcheckbox',
+            $completionattemptsexhaustedel,
+            null,
             get_string('completionattemptsexhausted', 'quiz'),
-            ['group' => 'cattempts']);
-        $mform->disabledIf('completionattemptsexhausted', 'completionpassgrade', 'notchecked');
-        $items[] = 'completionattemptsexhausted';
+            ['group' => 'cattempts']
+        );
+        $completionpassgradeel = 'completionpassgrade' . $suffix;
+        $mform->disabledIf($completionattemptsexhaustedel, $completionpassgradeel, 'notchecked');
+        $items[] = $completionattemptsexhaustedel;
 
         $group = [];
-        $group[] = $mform->createElement('checkbox', 'completionminattemptsenabled', '',
-            get_string('completionminattempts', 'quiz'));
-        $group[] = $mform->createElement('text', 'completionminattempts', '', ['size' => 3]);
-        $mform->setType('completionminattempts', PARAM_INT);
-        $mform->addGroup($group, 'completionminattemptsgroup', get_string('completionminattemptsgroup', 'quiz'), [' '], false);
-        $mform->disabledIf('completionminattempts', 'completionminattemptsenabled', 'notchecked');
-
-        $items[] = 'completionminattemptsgroup';
+        $completionminattemptsenabledel = 'completionminattemptsenabled' . $suffix;
+        $group[] = $mform->createElement(
+            'checkbox',
+            $completionminattemptsenabledel,
+            '',
+            get_string('completionminattempts', 'quiz')
+        );
+        $completionminattemptsel = 'completionminattempts' . $suffix;
+        $group[] = $mform->createElement('text', $completionminattemptsel, '', ['size' => 3]);
+        $mform->setType($completionminattemptsel, PARAM_INT);
+        $completionminattemptsgroupel = 'completionminattemptsgroup' . $suffix;
+        $mform->addGroup($group, $completionminattemptsgroupel, get_string('completionminattemptsgroup', 'quiz'), ' ', false);
+        $mform->disabledIf($completionminattemptsel, $completionminattemptsenabledel, 'notchecked');
+        $items[] = $completionminattemptsgroupel;
 
         return $items;
     }
@@ -635,8 +656,9 @@ class mod_quiz_mod_form extends moodleform_mod {
      * @return bool True if one or more rules is enabled, false if none are.
      */
     public function completion_rule_enabled($data) {
-        return  !empty($data['completionattemptsexhausted']) ||
-                !empty($data['completionminattemptsenabled']);
+        $suffix = $this->get_suffix();
+        return  !empty($data['completionattemptsexhausted' . $suffix]) ||
+                !empty($data['completionminattemptsenabled' . $suffix]);
     }
 
     /**
diff --git a/mod/scorm/mod_form.php b/mod/scorm/mod_form.php
index b45ef67ced0..cb1748d0aa0 100644
--- a/mod/scorm/mod_form.php
+++ b/mod/scorm/mod_form.php
@@ -271,8 +271,10 @@ class mod_scorm_mod_form extends moodleform_mod {
         $this->standard_coursemodule_elements();
 
         // A SCORM module should define this within itself and is not needed here.
-        if ($mform->elementExists('completionpassgrade')) {
-            $mform->removeElement('completionpassgrade');
+        $suffix = $this->get_suffix();
+        $completionpassgradeel = 'completionpassgrade' . $suffix;
+        if ($mform->elementExists($completionpassgradeel)) {
+            $mform->removeElement($completionpassgradeel);
         }
 
         // Buttons.
@@ -332,24 +334,29 @@ class mod_scorm_mod_form extends moodleform_mod {
         }
 
         // Set some completion default data.
+        $suffix = $this->get_suffix();
+        $completionstatusrequiredel = 'completionstatusrequired' . $suffix;
         $cvalues = array();
-        if (empty($this->_instance)) {
-            // When in add mode, set a default completion rule that requires the SCORM's status be set to "Completed".
-            $cvalues[4] = 1;
-        } else if (!empty($defaultvalues['completionstatusrequired']) && !is_array($defaultvalues['completionstatusrequired'])) {
+        if (!empty($defaultvalues[$completionstatusrequiredel]) && !is_array($defaultvalues[$completionstatusrequiredel])) {
             // Unpack values.
             foreach (scorm_status_options() as $key => $value) {
-                if (($defaultvalues['completionstatusrequired'] & $key) == $key) {
+                if (($defaultvalues[$completionstatusrequiredel] & $key) == $key) {
                     $cvalues[$key] = 1;
                 }
             }
-        }
-        if (!empty($cvalues)) {
-            $defaultvalues['completionstatusrequired'] = $cvalues;
+        } else if (empty($this->_instance)) {
+            // When in add mode, set a default completion rule that requires the SCORM's status be set to "Completed".
+            $cvalues[4] = 1;
         }
 
-        if (!isset($defaultvalues['completionscorerequired']) || !strlen($defaultvalues['completionscorerequired'])) {
-            $defaultvalues['completionscoredisabled'] = 1;
+        if (!empty($cvalues)) {
+            $defaultvalues[$completionstatusrequiredel] = $cvalues;
+        }
+
+        $completionscorerequiredel = 'completionscorerequired' . $suffix;
+        if (!isset($defaultvalues[$completionscorerequiredel]) || !strlen($defaultvalues[$completionscorerequiredel])) {
+            $completionscoredisabledel = 'completionscoredisabled' . $suffix;
+            $defaultvalues[$completionscoredisabledel] = 1;
         }
     }
 
@@ -447,15 +454,18 @@ class mod_scorm_mod_form extends moodleform_mod {
                 $errors['timeclose'] = get_string('closebeforeopen', 'scorm');
             }
         }
-        if (!empty($data['completionstatusallscos'])) {
+        $suffix = $this->get_suffix();
+        $completionstatusallscosel = 'completionstatusallscos' . $suffix;
+        if (!empty($data[$completionstatusallscosel])) {
+            $completionstatusrequiredel = 'completionstatusrequired' . $suffix;
             $requirestatus = false;
             foreach (scorm_status_options(true) as $key => $value) {
-                if (!empty($data['completionstatusrequired'][$key])) {
+                if (!empty($data[$completionstatusrequiredel][$key])) {
                     $requirestatus = true;
                 }
             }
             if (!$requirestatus) {
-                $errors['completionstatusallscos'] = get_string('youmustselectastatus', 'scorm');
+                $errors[$completionstatusallscosel] = get_string('youmustselectastatus', 'scorm');
             }
         }
 
@@ -490,27 +500,31 @@ class mod_scorm_mod_form extends moodleform_mod {
     }
 
     public function add_completion_rules() {
+        $suffix = $this->get_suffix();
         $mform =& $this->_form;
         $items = array();
 
         // Require score.
-        $group = array();
-        $group[] =& $mform->createElement('text', 'completionscorerequired', '', array('size' => 5));
+        $group = [];
+        $completionscorerequiredel = 'completionscorerequired' . $suffix;
+        $group[] =& $mform->createElement('text', $completionscorerequiredel, '', ['size' => 5]);
         $group[] =& $mform->createElement('checkbox', 'completionscoredisabled', null, get_string('disable'));
-        $mform->setType('completionscorerequired', PARAM_INT);
-        $mform->addGroup($group, 'completionscoregroup', get_string('completionscorerequired', 'scorm'), '', false);
-        $mform->addHelpButton('completionscoregroup', 'completionscorerequired', 'scorm');
-        $mform->disabledIf('completionscorerequired', 'completionscoredisabled', 'checked');
-        $mform->setDefault('completionscorerequired', 0);
+        $mform->setType($completionscorerequiredel, PARAM_INT);
+        $completionscoregroupel = 'completionscoregroup' . $suffix;
+        $mform->addGroup($group, $completionscoregroupel, get_string('completionscorerequired', 'scorm'), '', false);
+        $mform->addHelpButton($completionscoregroupel, 'completionscorerequired', 'scorm');
+        $mform->disabledIf($completionscorerequiredel, 'completionscoredisabled', 'checked');
+        $mform->setDefault($completionscorerequiredel, 0);
 
-        $items[] = 'completionscoregroup';
+        $items[] = $completionscoregroupel;
 
         // Require status.
         $first = true;
         $firstkey = null;
+        $completionstatusrequiredel = 'completionstatusrequired' . $suffix;
         foreach (scorm_status_options(true) as $key => $value) {
             $name = null;
-            $key = 'completionstatusrequired['.$key.']';
+            $key = $completionstatusrequiredel . '['.$key.']';
             if ($first) {
                 $name = get_string('completionstatusrequired', 'scorm');
                 $first = false;
@@ -522,18 +536,20 @@ class mod_scorm_mod_form extends moodleform_mod {
         }
         $mform->addHelpButton($firstkey, 'completionstatusrequired', 'scorm');
 
-        $mform->addElement('checkbox', 'completionstatusallscos', get_string('completionstatusallscos', 'scorm'));
-        $mform->setType('completionstatusallscos', PARAM_BOOL);
-        $mform->addHelpButton('completionstatusallscos', 'completionstatusallscos', 'scorm');
-        $mform->setDefault('completionstatusallscos', 0);
-        $items[] = 'completionstatusallscos';
+        $completionstatusallscosel = 'completionstatusallscos' . $suffix;
+        $mform->addElement('checkbox', $completionstatusallscosel, get_string('completionstatusallscos', 'scorm'));
+        $mform->setType($completionstatusallscosel, PARAM_BOOL);
+        $mform->addHelpButton($completionstatusallscosel, 'completionstatusallscos', 'scorm');
+        $mform->setDefault($completionstatusallscosel, 0);
+        $items[] = $completionstatusallscosel;
 
         return $items;
     }
 
     public function completion_rule_enabled($data) {
-        $status = !empty($data['completionstatusrequired']);
-        $score = empty($data['completionscoredisabled']) && strlen($data['completionscorerequired']);
+        $suffix = $this->get_suffix();
+        $status = !empty($data['completionstatusrequired' . $suffix]);
+        $score = empty($data['completionscoredisabled' . $suffix]) && strlen($data['completionscorerequired' . $suffix]);
 
         return $status || $score;
     }
@@ -550,8 +566,9 @@ class mod_scorm_mod_form extends moodleform_mod {
         parent::data_postprocessing($data);
         // Convert completionstatusrequired to a proper integer, if any.
         $total = 0;
-        if (isset($data->completionstatusrequired) && is_array($data->completionstatusrequired)) {
-            foreach ($data->completionstatusrequired as $state => $value) {
+        $suffix = $this->get_suffix();
+        if (isset($data->{'completionstatusrequired' . $suffix}) && is_array($data->{'completionstatusrequired' . $suffix})) {
+            foreach ($data->{'completionstatusrequired' . $suffix} as $state => $value) {
                 if ($value) {
                     $total |= $state;
                 }
@@ -559,21 +576,21 @@ class mod_scorm_mod_form extends moodleform_mod {
             if (!$total) {
                 $total  = null;
             }
-            $data->completionstatusrequired = $total;
+            $data->{'completionstatusrequired' . $suffix} = $total;
         }
 
         if (!empty($data->completionunlocked)) {
             // Turn off completion settings if the checkboxes aren't ticked.
-            $autocompletion = isset($data->completion) && $data->completion == COMPLETION_TRACKING_AUTOMATIC;
+            $completion = $data->{'completion' . $suffix};
+            $autocompletion = isset($completion) && $completion == COMPLETION_TRACKING_AUTOMATIC;
 
-            if (!(isset($data->completionstatusrequired) && $autocompletion)) {
-                $data->completionstatusrequired = null;
+            if (!(isset($data->{'completionstatusrequired' . $suffix}) && $autocompletion)) {
+                $data->{'completionstatusrequired' . $suffix} = null;
             }
-            // Else do nothing: completionstatusrequired has been already converted
-            //             into a correct integer representation.
+            // Else do nothing: completionstatusrequired has been already converted into a correct integer representation.
 
-            if (!empty($data->completionscoredisabled) || !$autocompletion) {
-                $data->completionscorerequired = null;
+            if (!empty($data->{'completionscoredisabled' . $suffix}) || !$autocompletion) {
+                $data->{'completionscorerequired' . $suffix} = null;
             }
         }
     }
diff --git a/mod/survey/mod_form.php b/mod/survey/mod_form.php
index 5ba2bf86e93..3578829ae3c 100644
--- a/mod/survey/mod_form.php
+++ b/mod/survey/mod_form.php
@@ -58,10 +58,11 @@ class mod_survey_mod_form extends moodleform_mod {
         parent::data_postprocessing($data);
         if (!empty($data->completionunlocked)) {
             // Turn off completion settings if the checkboxes aren't ticked.
-            $autocompletion = !empty($data->completion) &&
-                $data->completion == COMPLETION_TRACKING_AUTOMATIC;
-            if (!$autocompletion || empty($data->completionsubmit)) {
-                $data->completionsubmit = 0;
+            $suffix = $this->get_suffix();
+            $completion = $data->{'completion' . $suffix};
+            $autocompletion = !empty($completion) && $completion == COMPLETION_TRACKING_AUTOMATIC;
+            if (!$autocompletion || empty($data->{'completionsubmit' . $suffix})) {
+                $data->{'completionsubmit' . $suffix} = 0;
             }
         }
     }
@@ -72,19 +73,21 @@ class mod_survey_mod_form extends moodleform_mod {
      */
     public function add_completion_rules() {
         $mform =& $this->_form;
-        $mform->addElement('checkbox', 'completionsubmit', '', get_string('completionsubmit', 'survey'));
+        $suffix = $this->get_suffix();
+        $completionsubmitel = 'completionsubmit' . $suffix;
+        $mform->addElement('checkbox', $completionsubmitel, '', get_string('completionsubmit', 'survey'));
         // Enable this completion rule by default.
-        $mform->setDefault('completionsubmit', 1);
-        return array('completionsubmit');
+        $mform->setDefault($completionsubmitel, 1);
+        return [$completionsubmitel];
     }
 
     /**
      * Enable completion rules
-     * @param stdclass $data
-     * @return array
+     * @param array $data
+     * @return bool
      */
     public function completion_rule_enabled($data) {
-        return !empty($data['completionsubmit']);
+        $suffix = $this->get_suffix();
+        return !empty($data['completionsubmit' . $suffix]);
     }
 }
-