问题
选择题
---Sorry, Professor Smith. I didn’t finish the assignment yesterday.
---Oh, you___________ have done it as yesterday was the deadline.
A．must
B．mustn’t
C．should
D．shouldn’t
答案
答案：C
本题考查的是虚拟语气。此处表示和过去事实相反的情况，应该用should + have + 过去分词。本来应该做，而未做。选C。