问题补充:
----You didn’t wait for Mr. Smith last night, did you?
---- Yes, but we . He didn’t return home at all.
A. needn’t have
B. should have
C. didn’t need to
D. don’t have to
答案:
A. needn’t have
B. should have
C. didn’t need to
D. don’t have to
解析:句意:昨天晚上你没有等斯密斯先生,是吗?--不,我们等了,但是我们本来没有必要等,他根本没有回家。这句话重点是反意问句的回答,这里的Yes,说明是等了,所以用needn’t have done过去本不必做而实际上是做了,如果是didn’t need to,就是“过去不必做(也没有做),don’t have to=needn’t do,should have done本应该做却没做,所以选A。