We used to have a discussion ?A. did youB. didn’t weC. used weD. didn't used we

问题补充：

We used to have a discussion, ?

A. did you

B. didn’t we

C. used we

D. didn used we

答案：

A. did you

(答案→)B. didn’t we

C. used we

D. didn used we

解析：used可看成了行为动词，因此这里要用didn’t we。