---Why didn’t you reared him of the possible danger?
---But what otherwise? He never listens to me.
A. could I do
B. could I have done
C. should I do
D. must I have done
网友回答
A. could I do
(答案→)B. could I have done
C. should I do
D. must I have done
解析：考查虚拟语气：句意：——你为什么不告诉他可能的危险？——但是告诉他又能怎样？他从来不听我的。otherwise相当于if I had reminded him of the the possible danger可知是和过去事实相反的虚拟语气，要排除A和C。must have done是对过去的事情的推测，could have done可以是对过去的虚拟。选B。