问题补充:
-----Were you at home at 9 o’clock last night?
-----Yes, I a shower at that time.
A. took
B. was taking
C. was taken
D. am taking
答案:
A. took
(答案→)B. was taking
C. was taken
D. am taking
解析:句意:昨晚九点钟你在家吗?——是的,那时我正在洗澡。结合语境可知下文描述的是过去某时正在进行的动作,故用过去进行时态。选B。