didn't need to do表示过去不必做某事, 事实上也没做;needn't have done表示过去不必做某事, 但事实上做了
John went to the station with the car to meet Mary, so she didn't need to walk back home.
约翰开车去车站接玛丽,所以她不必步行回家了
John went to the station with the car to meet Mary, so she needn't have walked back home.
约翰开车去车站接玛丽,所以她本不必步行回家了。 (Mary步行回家了,没有遇上John的车)
【典型例题】
There was plenty of time. She ___.
A. mustn't have hurried
B. couldn't have hurried
C. must not hurry
D. needn't have hurried
【解析】 D needn't have done. 意为"本不必",即已经做了某事,而时实际上不必要。Mustn't have done 用法不正确,对过去发生的事情进行否定性推断应为couldn't have done, "不可能已经"。must not do 不可以(用于一般现在时)
7. 不定式的完成时用在 intend , mean , plan , suppose 等动词后,表示原打算做而实际未能做而实际未能做成的事,因而含有虚拟的意思
8. need / needn’t + have done 结构也可以表示虚拟语气,作‘本来有/没有必要做某事’
9. as it were 常插在句子中,表示‘姑且这样说,可说是’这类的意思
【2017高考英语备考复习:情态动词和虚拟语气3】相关文章:
★ 湖南省汝城二中2014届高考英语一轮复习阅读训练 (52)
★ 湖南省汝城二中2014届高考英语一轮复习阅读训练 (49)
★ 湖南省汝城二中2014届高考英语一轮复习阅读训练 (60)
最新
2017-04-24
2017-04-24
2017-04-24
2017-04-24
2017-04-21
2017-04-21