The meeting _ by the time I got there yesterday.A. was onB. has been onC. had begunD. has

问题补充：

The meeting _ by the time I got there yesterday.

A. was on

B. has been on

C. had begun

D. has begun

答案：

A. was on

B. has been on

(答案→)C. had begun

D. has begun

解析：时态的考察“我昨天到哪儿”是过去，“会议开始在我到哪儿之前”应是过去的过去。故用过去完成时。