试卷第一次调分评语没有出现

app/controllers/exercise_questions_controller.rb

@@ -525,7 +525,8 @@ class ExerciseQuestionsController < ApplicationController
               :score => @c_score,
               :answer_text => ""
             }
-            ExerciseAnswer.create(answer_option)
+            ex_answers = ExerciseAnswer.new(answer_option)
+            ex_answers.save
             ex_answer_old = 0
           end
           if ex_obj_score <= 0.0
@@ -625,7 +626,7 @@ class ExerciseQuestionsController < ApplicationController
           @exercise_current_user.update_attributes(ex_scores)
         end
         comments = params[:comment]
-        question_comment = @exercise_question.exercise_answer_comments.first
+        question_comment = @exercise_question.exercise_answer_comments&.first
         if question_comment.present?
           comment_option = {
               :comment => comments.present? ? comments : question_comment.comment,