. Research findings show we spend about two hours dreaming every night no matter what we

问题补充：

. Research findings show we spend about two hours dreaming every night, no matter what we have done during the day.

A. should

B. would

C. may

D. must

答案：

A. should

B. would

(答案→)C. may

D. must

解析：考查情态动词。句意“研究结果显示，我们每晚要花两个小时的时间做梦，无论白天做了什么事情。”should have done“本应该做某事”；would have done用于对过去事实的虚拟；may have done“可能已经做了某事”；must have done“一定已经做了某事”。这里表示“可能”。故选C。