Question

--I didn't see you at the meeting yesterday, why?

--I ________ for a long distance call then from my daughter in Canada.

1. A.
   waited
2. B.
   have waited
3. C.
   was waiting
4. D.
   will wait

Answer 1

C
此题题眼为then，相当于at that time。句意为“我昨天没在会上是由于我在等一个长途电话，”表示“过去某个时刻正在干什么”应用过去进行时。