题目内容：

The speaker________have criticized the paraprofessionals,knowing full that they were seated in the audience.
A should not to
B must not
C ought not to
D may not
该选什么?为什么?

优质解答

1. 答案：C. 2. 翻译：这个演讲者既然完全知道观众席上就有专业人员助手,他就本不该对他们提出批评. 3. 解释： 固定搭配：should not have done sth=ought not to have done sth 本不该做某事(但实际上已经做了) A 多了个to B 有must have done sth,但是没有must not have done sth； D 有may have done sth, 但是如果要表示否定,会用can't/couldn't have done sth,而没有may not have done sth.