问题补充:
You look very tired. You late last night.
A. needn’t sit up
B. didn’t need to sit up
C. shouldn’t sit up
D. needn’t have sat up
答案:
A. needn’t sit up
B. didn’t need to sit up
C. shouldn’t sit up
(答案→)D. needn’t have sat up
解析:考查情态动词。根据句意及时间状语,故用情态动词 + have done,needn’t have done本没有必要做,选D。