We the difficulty together but why didn’t you tell me?A. should faceB. might faceC. mus

问题补充：

We the difficulty together, but why didn’t you tell me?

A. should face

B. might face

C. must have faced

D. could have faced

答案：

A. should face

B. might face

C. must have faced

(答案→)D. could have faced

解析：考查虚拟语气。But后面的句子使用过去时，说明前面应该是与过去事实相反，用情态动词+have done表示与过去事实相反。