diff --git a/main/exercise/export/exercise_import.inc.php b/main/exercise/export/exercise_import.inc.php
index 6f1e4bbb6d..c066908c5d 100755
--- a/main/exercise/export/exercise_import.inc.php
+++ b/main/exercise/export/exercise_import.inc.php
@@ -11,7 +11,6 @@ use Chamilo\CoreBundle\Component\Utils\ChamiloApi;
  * @author Yannick Warnier <yannick.warnier@beeznest.com>
  */
 
-
 /**
  * Unzip the exercise in the temp folder
  * @param string The path of the temporary directory where the exercise was uploaded and unzipped
@@ -427,13 +426,13 @@ function startElementQti2($parser, $name, $attributes)
 
     switch ($current_element) {
         case 'ASSESSMENTITEM':
-            //retrieve current question
+            // retrieve current question
             $current_question_ident = $attributes['IDENTIFIER'];
-            $exercise_info['question'][$current_question_ident] = array();
-            $exercise_info['question'][$current_question_ident]['answer'] = array();
-            $exercise_info['question'][$current_question_ident]['correct_answers'] = array();
-            $exercise_info['question'][$current_question_ident]['title'] = $attributes['TITLE'];
-            $exercise_info['question'][$current_question_ident]['category'] = $attributes['CATEGORY'];
+            $exercise_info['question'][$current_question_ident] = [];
+            $exercise_info['question'][$current_question_ident]['answer'] = [];
+            $exercise_info['question'][$current_question_ident]['correct_answers'] = [];
+            $exercise_info['question'][$current_question_ident]['title'] = isset($attributes['TITLE']) ? $attributes['TITLE'] : '';
+            $exercise_info['question'][$current_question_ident]['category'] = isset($attributes['CATEGORY']) ? $attributes['CATEGORY'] : '';
             $exercise_info['question'][$current_question_ident]['tempdir'] = $questionTempDir;
             break;
         case 'SECTION':
@@ -444,11 +443,11 @@ function startElementQti2($parser, $name, $attributes)
             break;
         case 'RESPONSEDECLARATION':
             // Retrieve question type
-            if ("multiple" == $attributes['CARDINALITY']) {
+            if ('multiple' == $attributes['CARDINALITY']) {
                 $exercise_info['question'][$current_question_ident]['type'] = MCMA;
                 $cardinality = 'multiple';
             }
-            if ("single" == $attributes['CARDINALITY']) {
+            if ('single' == $attributes['CARDINALITY']) {
                 $exercise_info['question'][$current_question_ident]['type'] = MCUA;
                 $cardinality = 'single';
             }
@@ -540,21 +539,20 @@ function endElementQti2($parser, $name)
     if (sizeof($element_pile) >= 2) {
         $parent_element = $element_pile[sizeof($element_pile) - 2];
     } else {
-        $parent_element = "";
+        $parent_element = '';
     }
     if (sizeof($element_pile) >= 3) {
         $grand_parent_element = $element_pile[sizeof($element_pile) - 3];
     } else {
-        $grand_parent_element = "";
+        $grand_parent_element = '';
     }
     if (sizeof($element_pile) >= 4) {
         $great_grand_parent_element = $element_pile[sizeof($element_pile) - 4];
     } else {
-        $great_grand_parent_element = "";
+        $great_grand_parent_element = '';
     }
 
-    //treat the record of the full content of itembody tag :
-
+    //treat the record of the full content of itembody tag:
     if ($record_item_body && (!in_array($current_element, $non_HTML_tag_to_avoid))) {
         $current_question_item_body .= "</".$name.">";
     }
@@ -595,17 +593,17 @@ function elementDataQti2($parser, $data)
     if (sizeof($element_pile) >= 2) {
         $parent_element = $element_pile[sizeof($element_pile) - 2];
     } else {
-        $parent_element = "";
+        $parent_element = '';
     }
     if (sizeof($element_pile) >= 3) {
         $grand_parent_element = $element_pile[sizeof($element_pile) - 3];
     } else {
-        $grand_parent_element = "";
+        $grand_parent_element = '';
     }
     if (sizeof($element_pile) >= 4) {
         $great_grand_parent_element = $element_pile[sizeof($element_pile) - 4];
     } else {
-        $great_grand_parent_element = "";
+        $great_grand_parent_element = '';
     }
 
     //treat the record of the full content of itembody tag (needed for question statment and/or FIB text:
@@ -1076,9 +1074,9 @@ function qtiProcessManifest($filePath)
             $specialHref = Database::escape_string(preg_replace('/_/', '-', strtolower($href)));
             $specialHref = preg_replace('/(-){2,8}/', '-', $specialHref);
 
-            $sql = "SELECT iid FROM ".$tableDocuments." 
+            $sql = "SELECT iid FROM $tableDocuments 
                     WHERE
-                        c_id = " . $course['real_id']." AND 
+                        c_id = ".$course['real_id']." AND 
                         session_id = $sessionId AND 
                         path = '/".$specialHref."'";
             $result = Database::query($sql);
diff --git a/main/exercise/export/exercise_import.php b/main/exercise/export/exercise_import.php
index 90853742b5..6fb1ca495e 100755
--- a/main/exercise/export/exercise_import.php
+++ b/main/exercise/export/exercise_import.php
@@ -1,5 +1,6 @@
 <?php
 /* For licensing terms, see /license.txt */
+
 /**
  * @copyright (c) 2001-2006 Universite catholique de Louvain (UCL)
  * @package chamilo.exercise
@@ -16,16 +17,10 @@ if (api_is_platform_admin()) {
 
 require_once 'exercise_import.inc.php';
 
-//SQL table name
-
 $tbl_exercise = Database::get_course_table(TABLE_QUIZ_TEST);
 $tbl_question = Database::get_course_table(TABLE_QUIZ_QUESTION);
 $tbl_rel_exercise_question = Database::get_course_table(TABLE_QUIZ_TEST_QUESTION);
 
-// tool libraries
-
-//Tool title
-
 $nameTools = get_lang('ImportExercise');
 $interbredcrump[] = array('url' => '../exercise.php', 'name' => get_lang('Exercises'));
 
@@ -35,17 +30,17 @@ $cmd = (isset($_REQUEST['cmd']) ? $_REQUEST['cmd'] : 'show_import');
 switch ($cmd) {
     case 'show_import':
         $display = '<p>'
-            .            get_lang('Imported exercises must consist of a zip or an XML file (IMS-QTI) and be compatible with your Claroline version.').'<br>'
-            .            '</p>'
-            .            '<form enctype="multipart/form-data" action="" method="post">'
-            .            '<input name="cmd" type="hidden" value="import" />'
-            .            '<input name="uploadedExercise" type="file" /><br><br>'
-            .            get_lang('Import exercise').' : '
-            .            '<input value="'.get_lang('Ok').'" type="submit" /> '
-            .            claro_html_button($_SERVER['PHP_SELF'], get_lang('Cancel'))
-            .            '<br><br>'
-            .            '<small>'.get_lang('Max file size').' :  2&nbsp;MB</small>'
-            .            '</form>';
+            .get_lang('Imported exercises must consist of a zip or an XML file (IMS-QTI) and be compatible with your Claroline version.').'<br>'
+            .'</p>'
+            .'<form enctype="multipart/form-data" action="" method="post">'
+            .'<input name="cmd" type="hidden" value="import" />'
+            .'<input name="uploadedExercise" type="file" /><br><br>'
+            .get_lang('Import exercise').' : '
+            .'<input value="'.get_lang('Ok').'" type="submit" /> '
+            .claro_html_button($_SERVER['PHP_SELF'], get_lang('Cancel'))
+            .'<br><br>'
+            .'<small>'.get_lang('Max file size').' :  2&nbsp;MB</small>'
+            .'</form>';
         break;
     case 'import':
         //include needed librabries for treatment
@@ -67,10 +62,10 @@ include api_get_path(SYS_INC_PATH).'/header.inc.php';
 Display::display_introduction_section(
     TOOL_QUIZ,
     array(
-		'CreateDocumentWebDir' => api_get_path(WEB_COURSE_PATH).api_get_course_path().'/document/',
+        'CreateDocumentWebDir' => api_get_path(WEB_COURSE_PATH).api_get_course_path().'/document/',
         'CreateDocumentDir' => '../../..'.api_get_path(REL_COURSE_PATH).api_get_course_path().'/document/',
-		'BaseHref' => api_get_path(WEB_COURSE_PATH).api_get_course_path().'/'
-	)
+        'BaseHref' => api_get_path(WEB_COURSE_PATH).api_get_course_path().'/'
+    )
 );
 
 // Display Forms or dialog box(if needed)
diff --git a/main/exercise/export/qti2/qti2_classes.php b/main/exercise/export/qti2/qti2_classes.php
index 71c414005b..5cef6d5f75 100755
--- a/main/exercise/export/qti2/qti2_classes.php
+++ b/main/exercise/export/qti2/qti2_classes.php
@@ -331,7 +331,7 @@ class ImsAnswerHotspot extends Answer
                         $type = 'poly';
                         $coords = str_replace(array(';', '|'), array(',', ','), $answer['hotspot_coord']);
                         break;
-                     case 'delineation':
+                    case 'delineation':
                         $type = 'delineation';
                         $coords = str_replace(array(';', '|'), array(',', ','), $answer['hotspot_coord']);
                         break;
@@ -366,7 +366,7 @@ class ImsAnswerHotspot extends Answer
         $out .= '    </correctResponse>'."\n";
         $out .= '  </responseDeclaration>'."\n";
 
-       return $out;
+        return $out;
     }
 }
 
diff --git a/main/exercise/export/qti2/qti2_export.php b/main/exercise/export/qti2/qti2_export.php
index 847799b199..59224528a7 100755
--- a/main/exercise/export/qti2/qti2_export.php
+++ b/main/exercise/export/qti2/qti2_export.php
@@ -487,6 +487,7 @@ function formatExerciseQtiTitle($text)
 
 /**
  * @param string $text
+ * @return  string
  */
 function cleanAttribute($text)
 {