Question

【题目】Had they known what was coming next, they________ second thoughts.

A. may have

B. could have

C. must have had

D. might have had

Answer 1

【答案】D

【解析】本题考查虚拟语气的用法。本句是一个倒装句，可还原为：if they had known what was coming next, they might have had second thought。根据had known提示，可知是与过去事实相反，因此虚拟语气主句中应该用would/might have done，由此可见答案D符合语境。