Question

-Hi, Jack! Have you heard of any good news about Frank recently?

-Yeah．He ________ have done better．He has been admitted to Beijing University because of his winning the prize in the national computer contest．

1. A.
   shouldn't
2. B.
   wouldn't
3. C.
   needn't
4. D.
   couldn't

Answer 1

D
考查情态动词的用法。根据句意可知此处是表示能力，could have done：本来有能力做某事。本题用否定的比较级表示最高级的意思，意思为他已经取得了最好的成绩。shouldn't have done的意思为本来不该做某事而实际上做了；needn't have done本不需要做某事；wouldn't have done本不会做某事。