You should have gone over your lessons. (In fact you didn't go over your lessons.)你们应把功课复习好的。(可事实上你们没有。)
You shouldn't have watched TV last night. (In fact you watched TV last night.)你们昨天晚上本不该看电视。(可你们看了。)
You oughtn't to have entered the teachers' office without permission.没有经过允许,你们本不该进老师的办公室。
You oughtn't to have gone to the deserted place alone. 你不该独自去那荒凉之地。