问题补充:
---I wonder why Mr Green hasn’t showed up at the meeting yet.
---I’m not sure, but he in a traffic jam driving here.
A. could be stuck
B. might stuck
C. might have been stuck
D. must have stuck
答案:
A. could be stuck
B. might stuck
(答案→)C. might have been stuck
D. must have stuck
解析:表示对过去已经发生事情的推测应该用情态动词的完成时形式,但might的可能性不大;结合上下文的意思可以知道应该用被动形式。