diff --git a/app/views/courses/_course_activity.html.erb b/app/views/courses/_course_activity.html.erb
index bdbcabff0..763748ad7 100644
--- a/app/views/courses/_course_activity.html.erb
+++ b/app/views/courses/_course_activity.html.erb
@@ -50,7 +50,7 @@
 </script>
 <style type="text/css">
 </style>
-<% course_activities.each do |activity| if course_activities %>
+<% course_activities.includes(:course_act).each do |activity| if course_activities %>
         <script>
             function expand_reply(container, btnid) {
                 var target = $(container);
@@ -73,7 +73,7 @@
                 sd_create_editor_from_data(<%= activity.id%>, null, "100%", "<%= activity.class.to_s %>");
             });
         </script>
-            <% if activity && activity.course_act%>
+            <% if activity && activity.course_act %>
                 <% act = activity.course_act %>
                 <% case activity.course_act_type.to_s %>
                 <% when 'HomeworkCommon' %>
diff --git a/app/views/users/_course_homework.html.erb b/app/views/users/_course_homework.html.erb
index ee49e3cfc..e14132e85 100644
--- a/app/views/users/_course_homework.html.erb
+++ b/app/views/users/_course_homework.html.erb
@@ -151,7 +151,7 @@
           <% else %>
             <% student_works = activity.student_works.select("student_works.*,IF(final_score is null,null,final_score - absence_penalty - late_penalty) as score").order("score desc") %>
           <% end %>
-          <% student_works.each_with_index do |sw, i| %>
+          <% student_works.includes(:user).each_with_index do |sw, i| %>
               <div class="fl mr10 w100" style="text-align:center;">
                 <a href="javascript:void(0);" class="linkBlue">
                   <% if User.current.member_of_course?(activity.course) || User.current.admin? || activity.is_open == 1 %>
diff --git a/app/views/users/_course_message.html.erb b/app/views/users/_course_message.html.erb
index de49ba57a..0ac756f71 100644
--- a/app/views/users/_course_message.html.erb
+++ b/app/views/users/_course_message.html.erb
@@ -113,7 +113,7 @@
     <%  if count > 0 %>
         <div class="" id="reply_div_<%= user_activity_id %>">
           <ul>
-            <% activity.children.reorder("created_on desc").each do |reply|%>
+            <% activity.children.includes(:author).reorder("created_on desc").each do |reply|%>
                 <script type="text/javascript">
                     $(function(){
                         showNormalImage('reply_content_<%= reply.id %>');
diff --git a/app/views/users/_user_homework_detail.html.erb b/app/views/users/_user_homework_detail.html.erb
index a196ee6c0..780b1c6eb 100644
--- a/app/views/users/_user_homework_detail.html.erb
+++ b/app/views/users/_user_homework_detail.html.erb
@@ -155,7 +155,7 @@
           <% else %>
               <% student_works = homework_common.student_works.select("student_works.*,IF(final_score is null,null,final_score - absence_penalty - late_penalty) as score").order("score desc") %>
           <% end %>
-          <% student_works.each_with_index do |sw, i| %>
+          <% student_works.includes(:user).each_with_index do |sw, i| %>
               <div class="fl mr10 w100" style="text-align:center;">
                 <a href="javascript:void(0);" class="linkBlue">
                   <% if User.current.member_of_course?(homework_common.course) || User.current.admin? || homework_common.is_open == 1 %>