Look at the young men. They the bus.A. are running forB. are runC. is runningD. run for

问题补充：

Look at the young men. They the bus.

A. are running for

B. are run

C. is running

D. run for

答案：

(答案→)A. are running for

B. are run

C. is running

D. run for

解析：此题重点考查现在进行时的基本构成；look，是现在进行时的基本标志。