问题补充：
I don’t understand why they don’t have the report. It to them a week ago.
A. is sent
B. was sent
C. will be sent
D. had been sent
答案：
A. is sent
(答案→)B. was sent
C. will be sent
D. had been sent
解析：句意：我 不知道他们为什么没有报告，它一个星期前就送给他们了。时间是a week ago，所以和一般过去式连用，而且the report和send是被动关系，所以选B。
