英语四级英语语法知识，在*，独立调查的题基本上沒有，可是语法知识点却围绕一整张考卷，下边是我为大伙儿梳理的专业知识，期待能够为大伙儿产生协助，一起来学习培训一下吧。
　　 16.9 need "无须做"和"本不应该做" didn't need to do表明： 以往无须做某件事, 实际上也没做。. needn't have done表明： 以往无须做某件事, 但实际上干了。 John went to the station with the car to meet Mary, so she didn't need to walk back home. 罗伯特驾车去地铁站接玛丽莱，因此 她无须徒步回家。

　　John went to the station with the car to meet Mary, so she needn't have walked back home. 罗伯特驾车去地铁站接玛丽莱，因此 她本无须徒步回家。 (Mary徒步回家了，沒有遇到John的车。) 典型性练习题 There was plenty of time. She ___. A. mustn't have hurried B. couldn't have hurriedC. must not hurry D. needn't have hurried 回答D。needn't have done. 意为"本无须"，即早已干了某件事，而时事实上多余。 Mustn't have done 使用方法有误，对以往产生的事儿开展否定性推论应是couldn't have done, "不太可能早已"。 must not do 不能(用以一般现在时)。