—That must have been a lot of work.
—Yeah, it us three days to finish it.
A. takes
B. had taken
C. took
D. was taking
网友回答
A. takes
B. had taken
(答案→)C. took
D. was taking
解析:句意:那肯定有很多工作要做。是的,完成它花费了我们三天的时间。must have been表示对过去的肯定推测,可知事情发生在过去,现在已经完成了,动作不再持续,只表示过去的某个动作,故选C