diff --git a/app/controllers/exercise_controller.rb b/app/controllers/exercise_controller.rb
index 3d6b4794f..9efcfc19d 100644
--- a/app/controllers/exercise_controller.rb
+++ b/app/controllers/exercise_controller.rb
@@ -345,7 +345,7 @@ class ExerciseController < ApplicationController
       end
     elsif eq.question_type == 2
       #多选题
-      ea = ExerciseAnswer.find_by_exercise_question_id_and_user_id(params[:exercise_question_id],User.current.id)
+      ea = ExerciseAnswer.find_by_exercise_choice_id_and_user_id(params[:exercise_choice_id],User.current.id)
       if ea.nil?
         #尚未答该题，添加答案
         ea = ExerciseAnswer.new
@@ -360,7 +360,7 @@ class ExerciseController < ApplicationController
         end
       else
         #pv不为空，则当前选项之前已被选择，再次点击则是不再选择该项，故删除该答案
-        if pv.delete
+        if ea.delete
           @percent = get_percent(@exercise, User.current)
           render :json => {:text => "false" ,:percent => format("%.2f" , @percent)}
         else