He must have been late for the conference yesterday ?A. didn’t heB. hasn’t heC. mustn’t

问题补充：

He must have been late for the conference yesterday, ?

A. didn’t he

B. hasn’t he

C. mustn’t he

D. wasn’t he

答案：

A. didn’t he

B. hasn’t he

C. mustn’t he

(答案→)D. wasn’t he

解析：用must have done表示“对过去加以推测时”，其附加疑问部分要根据must后的动词形式和有无时间状语来确定用相应的时态。此句中动词是be，时间是yesterday，所以用wasnt he。如果去掉yesterday，就应选B项。