1、专题十 定语从句1定语从句用来说明主句中某一名词或代词（有时也可说明整个主句或主句中一部分）而起定语作用的句子叫作定语从句。一、关系代词引导的定语从句1. 关系代词用来指代先行词是人或物的名词或代词句子成分 用于限制从句或非限制性从句 只用于限制性从句代替人 代替物 代替人或物主语 Who which that主语 Whom which that宾语 Whose（=of whom） whose（=of which）This is the detective who came from London.The book which I am reading is written by Tomas
2、Hardy.The desk whose leg is broken is very old.This is the room that Shakespeare was born in.2.关系代词的用法（1）如果先行词是 all，much，anything ，something，nothing，everything，little，none 等不定代词，关系代词一般只用 that，不用 which.例如：All the people that are present burst into tears.（2）如果先等词被形容词最高级以及 first，last， any，only，few，mush
3、， no，some，very 等词修饰，关系代词常用 that，不用 which，who，或 whom.例如：（3）非限制性定语从句中，不能用关系代词 that，作宾语用的关系代词也不能省略。例如：There are about seven million people taking part in the election，most of whom、are well educated.（4）which 还有一种特殊用法，它可以引导从句修饰前面的整个主句，代替主句所表示的整体概念或部分概念。在这种从句中，which可以作主语，也可以作宾语或表语，多数情况下意思是与 and this 相似，并可
4、以指人。例如：He succeeded in the competition，which made his parents very happy.（5）that 可指人或物，在从句中作表语， （指人作主语时多用 who）仅用于限制性定语从句中。（6）which 可作表语，既可指人，以可指物。指人时，一般指从事某种职业或是有种特征。品性或才能的人。Which 引导的定语从句可以限制性的，也可以是非限制性的。（7）如果作先作词的集体名词着眼于集体的整体，关系代词用 which；若是指集体中的各个成员，则用 who.（8）先行词有两个，一个指人，一个指物，关系代词应该用 that.例如：The bo
5、y and the dog that are in the picture are very lovely.（9）如果先行词是 anyone，anybody，everyone，everybody，someone，somebody ，关系代词应该用 who 或 whom，不用 which.例如：Is there anyone here who will go with you？3.“介词关系代词”是一个普遍使用的结构（1） “介词关系代词”可以引导限制性定语从句，也可以引导非限制性定语从句。 “介词关系代词”结构中的介词可以是 in，on，about，from ，for，with，to at，o
6、f，without 等，关系代词只可用 whom 或 which，不可用 that .（2）from where 为“介词关系副词”结构，但也可以引导定语从句。例如：We stood at the top of the hill，from where we can see the town（3）像 listen to，look at，depend on，pay attention to，take care of 等固定短语动词，在定语从句中一般不宜将介词与动词分开。例如：专题十 定语从句2This is the boy whom she has taken care of.二、关系副词引导的定
7、语从句1.关系副词也可以引导定语从句关系副词在从句中分别表示时间。地点或原因。关系副词 when 在从句中充当时间状语，where 充当地点状语，why 充当原因状语。2. that 可引导定语从句表示时间。地点或原因That 有时可以代替关系副词 when，where 或者 why 引导定语从句表示时间。地点或原因，在 that 引导的这种定语从句中， that 也可以省去。三、限制性定语从句与非限制性定语从句1.二者差异比较限制定语从句紧跟先行词，同先行词这间一般不加逗号，仅修饰先行词，可以由关系代词。关系副词或 that 来引导。非限制性定语从句仅作补充或说明，用逗号与主句隔开，既可修饰
8、先行词，又可修饰整个主句，不可用 that 引导。2.关系代词和关系副词的选择依据（1） 弄清代替先行词的关系词在从句中作什么成分，作状语的应选用关系副词，作主语。宾语或表语的可选用关系代词。3.先行词与定语从句隔离定语从句一般紧跟在先行词之后，但定语从句与先行词之间有时也会插入别的成分，构成先行词与定语从句的隔离。例如：1）This is the article written by him that Is poke to you about2）He was the only person in this country who was invited四、as 在定语从句中的用法1. 引导限
9、制性定语从句和非限制性定语从句（1）as 多与 such 或 the same 连用，可以代替先行词是人或物的名词。（2）as 也可单独使用，引导非限制性定语从句，作用相当于 which.例如：The elephants nose is like a snake，as anybody can see.（3）the same- that 与 the same -as 在意思上是不同的。2.as 引导的非限制性定语从句的位置as 引导的非限制性定语从句位置较灵活，可以位于主句前面。中间或后面，一般用逗号与主句隔开，但 which 所引导的非限制性定语从句只能放在主句之后。例如：（1）As is e
10、xpected，the England team won the football match.（2）The earth runs around the sun，as is known by everyone. 3.as, which 的比较1).在非限制性定语从句中，均可替代整个主句或句中某个部分，在从句中作主语，宾语，表语如从句在主句之后，两者皆可用They failed in the exam, as/which is natural.She seems a scientist, as/which in fact she is.Grammar is not a set of dead r
11、ules, which/as I have said before.2).如从句在主句之前，用 asAs we all know, his parents were killed in this war.As is known to all, the earth travels around the sun.3).如关系代词代表主句全句意思，有“正如 ”“就象 ”之意时，用 asWe won the match, as we had expected.He agreed to the plan, as was to be expected.4). 当先行项被 the same, such, s
12、o 修饰时，用 asThis is the same book as you bought yesterday.同类书 (比较：This is the same book that you bought yesterday.同一本书)Dont believe in such men as praise you to your face.I never give my students so difficult a question as no one can work 专题十 定语从句3out.5). 当从句内容对主句内容起消极作用，则用 whichThe young man cheated
13、his friend out of much money, which was disgraced.6). as 也可以用来引导非限制性定语从句， 用来指待一件事，这时它的位置可以放在句首、句中和句尾。He is an American, as/which we know from his accent.As we know from his accent, he is an American.He, as we know from his accent, is an American.As has been said above, grammar is not a set of dead rules.Grammar, as has been said above, is not a set of rules.Grammar is not a set of dead rules, as/which has been said above. 正如: As everyone knows, as you may still remember, as you said, as I can see, as has been mentioned above, as you may have heard, and etc.
