—We are worried about Tom. Why hasn’t he come back?—Don’t worry. He in a traffic jam.A. m

问题补充：

—We are worried about Tom. Why hasn’t he come back?

—Don’t worry. He in a traffic jam.

A. might be caught

B. may have been caught

C. can have been caught

D. should have been caught

答案：

A. might be caught

(答案→)B. may have been caught

C. can have been caught

D. should have been caught

解析：考查情态动词+完成式的用法：句意：--我们很担心汤姆。为什么他还没有来？--别担心，他有可能遇到交通堵塞了。May have done过去可能做了…，因为是be caught in“遇上了”，can 表示对过去的推测，一般用于否定和疑问句中，should have done过去本应该做却没有做，选B。