He was caught in a traffic jam and by the time he reached the airport his friend's plane ( ).A.has alread taken off B.had already taken off C.has been taken offD.had been taken off
问题描述：
He was caught in a traffic jam and by the time he reached the airport his friend's plane ( ).
A.has alread taken off B.had already taken off C.has been taken off
D.had been taken off
答
He was caught in a traffic jam and by the time he reached the airport his friend's plane (B
take off没有被动，，起飞
希望对你有帮助，没有清楚采纳.
答
这里考察的是“by the time”的用法，当这个短语后面接的是过去时，那么动词要用过去完成时，老师应该讲过。
再者，take off是没有被动式的，所以选B
答
答案选B.
解析：由句中的was caught可知该句为一般过去时,结合语境,可知当他赶到机场的时候,朋友的飞机已经起飞了,因此应该为过去完成时态,排除选项A和C.
take off表飞机起飞,不存在被动语态,因此排除选项D,所以选择B.