I'll go to the library as soon as I finish what I.A. was doingB. am doingC. have doneD. h

问题补充：

Ill go to the library as soon as I finish what I.

A. was doing

B. am doing

C. have done

D. had been doing

答案：

A. was doing

(答案→)B. am doing

C. have done

D. had been doing

解析：考查时态。句意：我一完成作者做的事情，就去图书馆。过去进行时指过去某一时刻正在发生的事情，排除A；C表完成，排除C；过去完成时指“过去的过去”，这里没有明显的过去的动作，排除D；故选B。