1、1一， 定语从句用来修饰，限定主句中某一名词或代词（有时也可以说明整个主句或主句中一部分）而起定语作用的句子被称为定语从句。二， 限定性定语从句如果先行词在从句中充当主语或宾语时，就要用关系代词来引导定语从句。用来引导定语从句的关系代词有：who, whom, that 指人；which, that 代替事物；代替人或物的所有格用whose.（一）关系代词 that, who1. That, who 用来指人，在从句中用作主语或宾语，可以互换使用；that 也可以用来指物，但是不能用 who 指物。2. 关系代词 who, that 在从句中做宾语时，常可省略。3. 关系代词在从句中作主语时，
2、从句谓语与先行词在人称和数上保持一致。All the students who come into the room need to take off their shoes.4. 一般说来，人们倾向于用 who 指人，用 that 指物，尤其在口语中。（二）关系代词 which, thatWhich，that 都可以指物，在从句中用作主语或宾语时可以互换使用；指人可用that，但不能用 which。（三）关系代词 whom, whose1. Whom, whose 指人，whom 是 who 的宾格，whose 是所有格，分别在从句中作宾语和定语。2. Whom 在非正式文体中可省略，也可用
3、 that 或 who 代替3. Whose 是 who 和 which 的所有格，可指人，也可指物或动物。4. 当 whose 用来指物时，whose=the+名词+of which/of which + the+ 名词The book whose cover is broken is yours.= the book the cover of which is broken is yours.5. 当 whose 用来指人时，whose=the +名词+of whom/of whom+the+名词I have seen that girl whose glasses are broken
4、before.=I have seen that girl the glasses of whom are broken before.（四）关系代词 which, whom1. which,whom 在从句中作介词的宾语。2. 介词一般放在 which，whom 之前，也可以放在从句的原位。若是从句中的谓语是含有介词的动词短语，则介词只能放在原来的位置上，介词不能提前，固定动词短语一般不拆分（look into, look for） 。This is the man to whom I spoke just now.=this is the man whom I spoke to just
5、now.This is the school in which he studied English for three years.I have found the book that he is looking for.3. That 在从句中可代替 who, whom, which 用来指人或物，但是，当介词前置时，指人只能用 whom, 不能用 who/that， 指物只能用 which, 不能用 that。而且，whom 或 which 不能省略。4. 介词不能前置时，口语中或非正式文体，在从句中作介词宾语的关系代词常常可以省略。I have found the book (that
6、/which)he is looking for.（五） that, which, who 引导限制性定语从句时的用法区别1. 当先行词是指物的不定代词如 all, much, little, few, everything, nothing, some, any, 2anything 等时，只能用 that 引导从句，而且在从句中作宾语时常常可省略。Everything that can be done has been done.Everything (that) you have taken from me must be returned.Is there anything (that
7、) you do not understand? 2. 当先行词是序数词或受序数词修饰时，只能用 that 引导从句 。It is the third time that you have arrived late this month.The second question that has something to do with pollution is the most difficult.3. 当先行词是最高级或者受最高级修饰时，只能用 that 引导从句。The first book that I read last term was an English novel.4. 当先行
8、词受 the very, the only, the right, just the, exactly the, no, none, every 之类的修饰时，只能用 that 而不用 which, who, whom 引导从句。Is Oxygen the only gas that helps fire burn?5. 先行词有两个以上，表示人和物，只能用 that，而不用 which 引导从句。They are talking about the singers and songs that they like best.6. 关系代词在从句中作前置介词的宾语时，用指物的 which 或指
9、人的 whom， 而不能用 that 或 who。This is the man to whom I spoke just now.7. 当先行词指人的不定代词如 everyone, everybody, anyone, anybody, nobody 等时，用 who, 而不用 that 引导从句。（六）关系代词 but（准关系代词）, what（复合关系代词）1. But 作为关系代词常与具有否定或疑问意义的主句连用，其引导的从句修饰的先行词多是否定意义的，but=whonot, which.not 或 thatnot， 意为“无不，没有不，谁不”Generally speaking, t
10、here is no one but(who not) loves their parents in the world.There is no rule but has exceptions.There is no rule that has not exceptions.没有任何规则是没有例外的。There is no one but knows about this affairThere is no one who doesnt know about this affair. 没有一个人不知道此事。There are few dictionaries but have a mispri
11、nt or two.There are few dictionaries that dont have a misprint or two. 几乎每本词典都有一两个印刷错误。2. What 引导定语从句时，即可指人也可指物，指人时 what=the person(s) that, 指物时 what=the thing/all/everything that.3. What 本身的作用已经包含有先行词和关系代词。 有一身兼两职的作用，分别在主句和从句中作相应的成分。A computer can only do what you have instructed it to do.4. 用 what
12、 时，前无先行词；若有先行词，应视其情况选择使用 that, which 或 who.This is exactly what I wanted.不说 this is the book what I want.应该说 this is the book that I want/ this is what I want.（七）关系代词 as1. As 即可指人也可指物，多与 such, the same 连用，构成 suchas, the same.as 的结构32. Such.as 意思为：“诸如之类的” ， as 在从句中可作主语，宾语或表语。Such people as were menti
13、oned by him were honest. (as 作主语)We have such grape as you never saw. (as 作宾语)Ive never seen such a clever man as he is.(as 做表语)3. The same as 意思为：“与相同的” ， as 在从句中可作主语，宾语或表语。Modern statesmen are often faced with the same problem as defeated the ancient Romans.(as 作主语)I like the same book as you do.
14、(as 作宾语)4. AsasAs many children as came were given some cakes .所有来的孩子都得到了蛋糕（as 做主语）He is as diligent a man as ever lived. (as 做主语)He was telling the kids as funny a story as he did last time(as 做宾语)注：suchas（诸如-之类的）与 suchthat（如此-以至于）的区别。Such.as 引导定语从句，such.that 引导结果状语从句They talked in such simple Engl
15、ish as children could understand. 他们用孩子们能听懂的简单英语交谈They talk in such simple English that children could understand. 他们十分简单的英语交谈，连孩子们都能听懂。I will provide you with such things as you may need.我要供给你一些你可能用得着的东西。He shut the window with such a force that the glass broke.他如此用力的关门，结果玻璃碎了。The same .as 与 the sa
16、methat 的区别 the same.as 指两物相似，the same.that 描述的是同一物。This is the same bag as I lost yesterday.这个书包和我昨天丢失的相似（相似物）This is the same bag that I lost yesterday.这正是我昨天丢失的那个书包。 （同一物）（八） 关系代词在从句中做主语时的主谓一致1. 从句谓语动词要与先行词在人称和数上保持一致。2. “One of +the+复数名词” 作先行词时，若 one 前面有限定词，从句谓语与 one保持一致；否则，从句谓语用复数。Mr. Herpin is o
17、ne of the foreign experts who are working in China.3. What 在从句中作主语，从句谓语一般用单数，或与主句表语保持一致。4. 集体名词作先行词根据意义一致原则，强调整体时从句谓语用单数，强调个体成员时，从句谓语用复数形式。The class which is in the next room is Class 5.The family who live upstairs are all model workers.（九） 关系副词1. 先行词指时间并在从句中作时间状语时，用 when 引导从句。When=in/at/on which.2.
18、 先行词是表示时间的名词，但在从句中作动词 remember, spend, take, forget 等4动词的宾语时，用 that 或 which 引导从句。3. 先行词指地点并在从句中作地点状语时，用 where 引导从句， where=in/at/on which。4. 当先行词是表示地点的名词，但在从句中作动词 visit, forget, remember, build 等动词的宾语时，用 that 或 which 而不用 where 引导从句。5. 当先行词是 case, situation, chair, circumstance 等名词，表示从句主语处于某种状况，境地，或阶段
19、时，用 where 引导从句。If a shop has chairs where women can park their men, women will spend more time in the shop.Hes got himself into a dangerous situation where he is likely to lose control over the plane.I can think of many cases where students obviously knew a lot of English words and expressions but c
20、ouldnt write a good essay.（十） 关系副词 why, that1. 先行词是 reason 在从句中作原因状语时，用关系副词 why 引导从句。Why= for which.2. 先行词是 reason 但是在从句中作某些动词如 explain, remember, forget 等的宾语时，不能用 why 引导从句，这时要用 that 或 which 引导从句。3. That 有时可用作关系副词，代替 where, when 或 why 引导从句，并且可以省略。4. 先行词是 the way 在从句中作方式状语，用 in which/that 引导从句或者不用关系词
21、。（十一） 关系副词和关系代词的选择三， 非限定性定语从句（一） 关系代词 as, which 引导修饰句子的定语从句，代表整个主句或主句的一部分。AS 引导的句子, 代表整个主句或主句的一部分（不能指代某个名词或代词） 。As is known to all, he is the best student in our class. As 指代整个句子，作主语He opposed the idea, as could be expected. As 指代整个句子，作主语Taiwan is, as you know, an inseparable part of China. As 指代整个句
22、子。主句具有否定意义，AS 引导的定语从句放在主句之后时，as 指代的主句不包括否定意义，可用 but 取代。Insects do not have bones, as people have./but people have bones.Whales are not fish, as some people think/but some people think they are.1. As 放在句首时，As 指代的主句仍包含否定意义。As has been said above, grammar is not a set of dead rules.正如前面所说的，语法不是一套死条文。2.
23、 Which 引导的句子, 代表整个主句或主句的一部分,不能用 that 替换。The sun, which had been hidden all day, now came out in its splendor.We were given a lovely double room, which had a sea view.3. As which 区别，which 引导的从句不能放在主句前，而 as 引导的从句则既可放在主句前，也可以放在主句之后。As (正确 ) is often the case, he is absent5Which (错误) is often the case, he is absent.He saw the girl, as he has hoped./which he had hoped 4. As, which 在从句中作主语时，其从句的谓语动词总是用第三人称单数。5. 从句是被动语态时，多用 AS 引导从句。6. 从句谓语是 know, see 等时一般用 as7. As 可用于 the same.as, such ,as 机构中，which 不能8. Which=and that 意味“这一点” ，当从句是否定的，从句谓语是系表结构或者从句的宾语是复合结构时多用 which 引导从句。6
