对于大学英语四六级考试来说,语法非常重要。坚实的语法是英语水平进阶的充分必要条件。但现实情况是,不少人对语法学习并没有一个清晰的概念,甚至忽视语法学习。在此小编希望考生们重视起最语法的复习。今天树图网给大家盘点2020年上半年大学英语六级语法:don't need和needn't,希望对您有所帮助。
大学英语六级语法:don't need和needn't
don'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,没有遇上John的车。)
There was plenty of time. She ___.
A. mustn't have hurried B. couldn't have hurriedC. must not hurry D. needn't have hurried
答案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)。
语法的学习过程会觉得条目繁多,很难记,而且枯燥无味,这种情况下,学习应该寻找的是语法的学习方法。掌握方法,在学习过程中才能克服困难。更多四级语法、六级语法请及时关注树图网站。