问题
选择题
By the time they arrived at the station, the train .
A.will leave
B.would leave
C.has left
D.had left
答案
答案:D
题目分析:句意:到他们到达火车站是,火车已经离开了。根据By the time they arrived at the station,可知到达这个动作发生在过去,火车离开是在他们到达之前,故用过去完成时。故选D。