—DidyouhearthatJackusedtobeapolicemanfortwoyears?  —Yo...

问题详情：

 —Did you hear that Jack used to be a policeman for two years?

   —You’re kidding! He ______, for he’s too short.

   A. can’t be         B. can’t have been       C. may not be     D. may not have been

【回答】

B

知识点：虚拟语气与情态动词

题型：选择题