作业帮一道关于情态动词的英语习题The had plenty of bread,so she__a loaf.A.needed not to buy B,need not to have bought C,needn't have bought D.didn't need to buy 这道题应该怎么判断选哪个?如何判断need是做情态动词还是实义
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一道关于情态动词的英语习题The had plenty of bread,so she__a loaf.A.needed not to buy B,need not to have bought C,needn't have bought D.didn't need to buy 这道题应该怎么判断选哪个?如何判断need是做情态动词还是实义
一道关于情态动词的英语习题
The had plenty of bread,so she__a loaf.
A.needed not to buy B,need not to have bought C,needn't have bought D.didn't need to buy 这道题应该怎么判断选哪个?如何判断need是做情态动词还是实义动词呢?如果做实义动词那么D的用法对吗?可以说是didn't need吗
一道关于情态动词的英语习题The had plenty of bread,so she__a loaf.A.needed not to buy B,need not to have bought C,needn't have bought D.didn't need to buy 这道题应该怎么判断选哪个?如何判断need是做情态动词还是实义
区别：needn't have done表示过去没必要做而实际上做了；
didn't need to do表示过去没必要做而实际上也没做.
根据前面的句子They had plenty of bread来判断,she没必要买面包而实际上买了,所以选C.
need 后面有to 的时候就是实义动词，没有to直接加动词原形的时候就是情态动词
我选D
根据had，可判断为过去式。need作实义动词后加动词不定式，作情态动词后加动词原型。needn't have done是指本不需要做而做了。根据句意及语法，可判断选D。
needn't = don't need to
所以A、B就是错的，而 have bought和 didn't 我个人认为是两个时态的不同。
have done表示对现在有影响，而did表示过去，并不强调影响有多大。
但本题句意相信你能看出来是有“影响”的。所以我选C！
记住：needn't = don't need to
也就是说need可以是情态动词，也可是一般动词，情态动词后跟动词原形。
知道这一点，就可以判断，A，B为错。
D错在没有have，因为该句是个虚拟语气，意为本不需要买的，但实际上买了。
所以该题属于考你对needn't have done这个虚拟语气的掌握。
Are you clear?...
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记住：needn't = don't need to
也就是说need可以是情态动词，也可是一般动词，情态动词后跟动词原形。
知道这一点，就可以判断，A，B为错。
D错在没有have，因为该句是个虚拟语气，意为本不需要买的，但实际上买了。
所以该题属于考你对needn't have done这个虚拟语气的掌握。
Are you clear?
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