一I heard that you got an A in the chemistry exam．Well done!
一Thanks，I know that you a good job as well．
A. shouId have done
B. need have done
C. must have done
D. could have done
网友回答
A. shouId have done
B. need have done
(答案→)C. must have done
D. could have done
解析：考查情态动词用法。A本应该做某事实际上去没有做；B本需要做实际上却未做；C一定做了某事；D本可以做却未做。句意—我听说在化学考试中你得了A。做得好。—谢谢。我知道你也一定做的很好。