3.(英语卷.2014届江苏省南京师大附中高三模拟考试)—What a pity! Their
experiment is a failure.
—They ________ better under more favorable
conditions.
A. should have done
B. could have done C. must have done
D. may have done
[答案] B
[解析]
试题分析: 句意:--真遗憾,他们的实验是一个失败.—在更加有利的条件下他们本应该做的更好。这里under more favorable conditions.是一个隐含的虚拟语气,相当于if they had been under more favorable conditions.说明是和过去相反的虚拟条件句,所以主句是could have done“过去本可以做的更好”,所以选B。
考点:考查含蓄的虚拟条件句