---Did you listen to the speech?No we it. But we had a lot of traffic on our way.A.

问题补充：

---Did you listen to the speech?

--- No, we it. But we had a lot of traffic on our way.

A. could have attended

B. must have attended

C. could attend

D. shouldn have attended

答案：

A. could have attended

B. must have attended

C. could attend

D. shouldn have attended

解析：该题考查的是虚拟语气，表示“本能……”是与过去事实相反，要用could+have done形式。