问题补充:
I my homework while my parents TV at 9 last night.
A. did; have watched
B. had done; were watching
C. was doing; were watching
D. would do; were watching
答案:
A. did; have watched
B. had done; were watching
(答案→)C. was doing; were watching
D. would do; were watching
解析:句意:昨天晚上九点钟当我父母看电视时,我在做作业。过去进行时表示过去某一时刻正在发生和进行的动作;故选C。