According to a recent poll,61 percent of American high schoo

According to a recent poll,61 percent of American high school students have admitted to cheating on exams at least once.It can be argued such a response may not mean much.After all,most students have been faced with the temptation to peek at a neighbor's test paper.And students can be hard on themselves in judging such behavior.However,there are other indications that high school cheating may be on the rise.
其中这句And students can be hard on themselves in judging such behavior
be hard on 是对什么严格的意思.在这里感觉讲不通,这些学生对自己严格在判定他们的行为上?
还是这些学生很难判定他们自己的这种行为,为什么很难判定自己的行为呢,感觉讲不通.

学生们可以对自己严格要求来判断这些行为.（因为大多数学生都面临偷看邻桌试卷的诱惑）