Question

Oh, I'm not feeling well in the stomach, I ________ so much fried chicken just now．

1. A.
   shouldn't eat
2. B.
   mustn't have eaten
3. C.
   shouldn't have eaten
4. D.
   mustn't eat

Answer 1

C
解析：
由just now而知，本題談論過去之事。談論過去之事，在should或must之后接不定式的完成式。must表示推測只用于肯定句中，shouldn’t have done表說話之前本不應該做某事，但事實上卻做了，含有責備的口氣。