---Has Tom finished his job yet?
---I have no idea of it; he it this morning.
A. has been doing
B. had been doing
C. did
D. was doing
网友回答
A. has been doing
B. had been doing
C. did
(答案→)D. was doing
解析：考查时态。表示过去某一时刻正在进行的动作用过去进行时态。句意：汤姆完成他的工作了吗？我不清楚，他整个上午一直在做。所以选D。