diff --git a/app/views/exercise/_exercise_student_result.html.erb b/app/views/exercise/_exercise_student_result.html.erb
index 7805cb60..a161ee7f 100755
--- a/app/views/exercise/_exercise_student_result.html.erb
+++ b/app/views/exercise/_exercise_student_result.html.erb
@@ -142,7 +142,7 @@
             <% if @show_score %>
               <% answer = get_user_answer(exercise_question, user) %>
               <p class="fr" id="question_score_<%= exercise_question.id %>">
-                <span class="<%= answer.empty? ? 'color-red' : (answer.first.score == -1 || answer.first.score == 0 ? "color-red" : "color-light-green") %> mr3"><%= answer.empty? ? 0 : (answer.first.score == -1 ? "未批" : answer.first.score) %></span><%= answer.empty? ? "分" : (answer.first.score == -1 ? "" : "分") %>
+                <span class="<%= answer.blank? ? 'color-red' : (answer.first.score == -1 || answer.first.score == 0 ? "color-red" : "color-light-green") %> mr3"><%= answer.empty? ? 0 : (answer.first.score == -1 ? "未批" : answer.first.score) %></span><%= answer.empty? ? "分" : (answer.first.score == -1 ? "" : "分") %>
               </p>
             <% end %>
           <% end %>
@@ -269,7 +269,7 @@
               </script>
             </div>
           <% end %>
-          <% if !answer.empty? %>
+          <% if !answer.blank? %>
             <% if @is_teacher %>
               <div class="clearfix padding15 bor-top-greyE" id="answer_comment_<%= answer.first.id %>">
                 <%= render :partial => "answer_comment", :locals => {:answer => answer.first, :exercise_question => exercise_question} %>