．—What’s the matter with the man hanging his head there? —Well if you know he was caugh

问题补充：

．—What’s the matter with the man hanging his head there?

—Well, if you know, he was caught stealing my bike.

A. must

B. may

C. can

D. shall

答案：

(答案→)A. must

B. may

C. can

D. shall

解析：考查情态动词must的用法，这里表示“偏要”，句意：--那边低着头的男子怎么了？--如果你偏要知道的话，他被抓住偷我的自行车。选A。