高中英语高考2021届人大附中高中英语新高考语法一轮复习讲义（11）than，as和but作关系代词用法知识点总结整理

这是一份高中英语高考2021届人大附中高中英语新高考语法一轮复习讲义（11）than，as和but作关系代词用法知识点总结整理，共5页。
2021届人大附中高中英语新高考语法一轮复习讲义（11）than，as和but作关系代词用法知识点总结整理than, as, but作准关系代词的用法关系代词通常是用来引导定语从句的，than, as和but除了做基本连词外还可以作准关系代词，但是与which，who,that等关系代词不同，than, as和but引导的定语从句与典型的定语从句不太相像，因此称它们为准关系代词。 Than,as,but作准关系代词条件是：前面必须有先行词（名词）例：I have more money than you do (我比你有钱)He has as much money as I do （他和我的钱一样多）There is nothing but he knows（没有什么他不知道的）我们分别进行详细说明：1.  Than 作准关系代词的用法Than 之前若有名词，则than = than + the + 前面的名词 + 关系代词（who, whom, which）,因此可以将than 视为关系代词。Than 作准关系代词通常出现在more …than,less…than, fewer…than等结构中，且在从句中可以充当主语，宾语和be动词后得表语。例1. I have more money than is needed.（than作从句的主语）= I have more money than the money which is needed （我现有的钱比所需要的多）例2. I have more money than he needs（than作从句的宾语）I have more money than the money which he needs（我现有的钱比他所需要的多）例3. heis a better student than you（ are ）.(than 作从句的表语)2.   As 作准关系代词的用法as之前若有名词，则as = as + the + 前面的名词 + 关系代词（who, whom, which）,因此可以将as 可视为关系代词，并在所引导的从句中作主语，宾语和be动词之后的表语。但只用于下列短语中：as作为准关系代词只能用于下列短语:1. Such+n. + as...例: I don't like such a man as tells lies(as作从句的主语)我不喜欢说谎的人2. The same+ n. + as...例: I have the same book as you bought yesterday(as作从句的宾语)我有一-本书和你昨天买的-样3. As+ adj. +n. + as...例1: he is as diligent a man as ever lived(as作从句的主语)他是有史以来最勤奋的人例2: he is as good a man as John (as 作从句的表语)他是个和约翰一样好的人注意：① such + n. 之后不可用like（像）加以修饰。Such a man like him is bad. (错)Such a man as him is bad.（对）② as 可替代主句。单独使用as时，as也可以作关系代词，等于which，用来代替整个主句。He is nice, which is known to us= he is nice , as is known to us(他人很好，我们都知道)③ as引导的从句可置于主句的前后，而which引导的从句只能置于主句之后。例. He is nice, as we all know= as we all know, he is nice④只能与单数可数名词使用的结构。只能与单数可数名词使用的结构:1.So .. that如...以至于......例:he is so good a boy that I like him2.As ... ...as 和.....样地.....例: he is as handsome a man as Peter (is)3.Too .. to ...太 ......而不....例:heistoooldamantodoit4.how...多么地例: how great a man he is3.   But 作为准关系代词的用法。But 作为准关系代词时，只用于“no + n.”之后，此时but等于who(whom, which )…not.即there is no + 名词 + who(whom, which, that)…not= there is no + 名词 + but……注意：定语从句中有be 动词保留be动词例：there is no one who is not interested in it.= there is no one but is interested in it(没有人不对他感兴趣) 定语从句中有助动词（can,will,may,should…）保留该助动词。There is nothing that he can not do=There is nothing but he can do（没有什么事是他做不来的） 定语从句中有do,does和did等助动词时，先去掉助动词，再依时态人称将之后的动词还原。There is no book which he doesn’t like to read= There is no book but he likes to read.