—You were out when I dropped in at your house.
—Oh, I for a friend from England at the airport.
A. was waiting
B. had waited
C. am waiting
D. has waited
网友回答
(答案→)A. was waiting
B. had waited
C. am waiting
D. has waited
解析：句意是：(你来我家时) 我正在机场等候一位从England来的朋友。表示在过去某一时刻或在过去某一段时间内正在发生的事，用过去进行时，所以选A。