【题目】-–Mary knows the city quite well.
--She______ well have been there before.
A.needB.couldC.shouldD.may
在线课程【答案】D
【解析】
考查情态动词辨析。句意：——Mary非常了解这个城市。——她肯定以前在那里呆过。may have done过去可能做过某事。表示对过去的肯定猜测。need have done本需要做某事却没做；could have done本可以做某事却没做；should have done本应该做某事却没做。故选D。