— Catherine, I have cleaned the room for you .
— Thanks. You . I could manage it myself.
A. needn’t do
B. needn’t have done
C. mustn’t do
D. shouldn’t have done
网友回答
A. needn’t do
(答案→)B. needn’t have done
C. mustn’t do
D. shouldn’t have done
解析：考查情态动词用法。句意：—Catherine，我帮你打扫了房间。—多谢，你本不必这样做的，我可以自己搞定。根据句意是对过去情况的虚拟。故使用“情态动词 have done”表示对过去情况的虚拟。Needn’t have done本不必做某事，实际上却做了；shouldn’t have done本不应该做某事，实际上却做了；故B正确。