定语从句中的(牛鼻子)

定语从句中的“牛鼻子”就是关联词。初学者由于抓住这个“牛算子”，往往会犯错误。本文将从以下12个方面谈谈如何抓定语从句中关联词这个“牛鼻子”。

1、抓住关系代词。从句中关系副词可由“介词+关系代词”代替，因此，掌握了关系代词，关系副词也就迎刃而解了。如：The boy didn't tell me the classroom where he was studying句中的where可由in which来取代。
2、从句中不能出现疑问句的形式。如The woman can't tell the day when her son was born句中的was不能放到when之后。
3、从句中不能出现疑问句的形式。如：Here is the pen that you lost it yesterday.句中的it指的就是先行词the pen，应删去it。
4、关系代词应与先行词在数上一致。如The gifts which were sent to Jack were very expensive.
5、关系代词在从句中可作主语、宾语和定语，关系副词只作状语。如That't the day when l'll never forget.句中的关联词应是forget的宾语，故不能用when，应用which或that.
6、可以换用的关系代词。
a.修饰物的关系代词用which或that；如：Abookstore is a store whic/that sells books.
b.修饰人的关系代词常用who,也可用that.如：The comrade who/that visited our class yeaterday is our new headmaster.
7、不能换用的关系代词。which不能修饰人;who不能悠物;whose作从句中的定语,既可修饰人,也可修饰物。如:The horse whose windows face south was built last year.
在下列情况下，须用that；
a.先行词为all、little、the、one、everything、something、nothing、anything等不定代词(something)后也可用which;如Is there anyting that l can do for you?The finger that l put into my mouth was not the one that l had dipped int omy cup.
b.先行词被序数或形容词最高级修饰时；如The last place that we visited was the library.
He is the meat careful boy that l Know.
c.先行词由"人+物"构成时。如:He talked of the men and the work that interested him very much.
且that不用于非限制性定语从句之中。如：Tom got the first place,which(不用that) pleased his parents.
8、可以省略的关系代词。当关系代词在从句中作宾语时，往往可以省略。如：The letter (that/which) l received yesterday was from my brother.
9、不可省略的关系代词。
a.在从句中作其他成分的关系代词，如：The boy who is playing on the grass is Jack's brother.
b.在非限制性定语从句中的关系代词，如That's Lao Li,whom k mentioned to you the other day.
c.介词位于关系代词之前时.如:This is the house in which Mr Smith once lived.
10、跟关系代词连用的介词可置于关系代词之前,也可置后.如上句也可改为T.is is the house which Mr
Smith once lived in.
还要注意：
a.that作介词宾语时，介词位于从句中原来的位置；如:Can you lend me the book that you were thlking about?
b.在非限制定语从句中，介词位于关系代词位置，如：Wu Dong,with whom
l went concert,enjoyed it very much.
c.伸词是短评动词的固定部分，不可拆开。如：Is this the dey that you are looking for?
11、which有时代表前面整个主句所表达的概念。如：The meeting was put lff,which was exactly what we wanted.
12、关系代词as常与such和the same连用。如：I have never seen such a wild dog as you describe.
I have the same trouble as you have.