定語從句
定語從句起了形容詞的作用，在句中修飾一個名詞或代詞。被修飾的詞叫做先行詞，引導定語從句的詞叫關系詞，他的作用一是放在先行詞與定語從句中間起了連接作用，二是在從句中擔當一個成分，并與先行詞保持數的一致。
定語從句掌握要點分析：一：掌握定語從句關系代詞和關系副詞的選用，以備選擇題；二：掌握定語從句的翻譯，以備閱讀及完形填空和填空題的理解；三：掌握簡單的定語從句的漢譯英，以備在作文中能寫出簡單的含定語從句的句子。
關系詞 先行詞 從句成分 例句 備注
關系代詞 who 人 主語 Do you know the man who is talking with your mother? whom, which和that在從句中做賓語時，常可以省略，但介詞提前時后面關系代詞不能省略，也不可以用that
whom 人 賓語 Mr. Smith is the person with whom I am working
The boy (whom) she loved died in the war..
whose 人，物 定語 I like those books whose topics(the topics of which) are about history.
The boy whose father works abroad is my deskmate.
that 人，物 主語，賓語 A plane is a machine that can fly.
She is the pop star (that) I want to see very much.
which 物 主語，賓語 The book (which) I gave you was worth $10.
The picture which was about the accident was terrible.
as 人，物 主語，賓語 He is such a person as is respected by all of us.
This is the same pen as I lost yesterday. as做賓語一般不省略
關系副詞 when 時間 時間狀語 I will never forget the day when we met there. 可用on which
where 地點 地點狀語 This is the house where I was born. 可用in which
why 原因 原因狀語 I can’t imagine the reason why he turned down my offer. 可用for which
II. that與which, who, whom的用法區別：
情況 用法說明 例句
只用that的情況 先行詞為all, everything, anything, nothing, little, much,等不定代詞時。
先行詞被all, any, every, each, much, little, no, some, few等修飾時
先行詞有形容詞最高級和序數詞修飾時
先行詞既指人又指物時
先行詞被the only, the very修飾時
句中已經有who或which時，為了避免重復時 1.He told me everything that he knows.
2.All the books that you offered has been given out.
3.This is the best film that I have ever read.
4.We talked about the persons and things that we remembered.
5.He is the only man that I want to see.
6.Who is the man that is making a speech?
只用which, who, whom的情況 在非限制性定語從句中，只能用which指代物，用who/whom指人
在由“介詞+關系代詞”引導的定語從句中，只能用which指物，whom指人。
先行詞本身是that時，關系詞用which, 先行詞為those, one, he時多用who。 He has a son, who has gone abroad for further study.
I like the person to whom the teacher is talking.
Those who respect others are usually respected by others.
一：定語從句關系代詞和關系副詞的選用：
掌握在一個句子中，定語從句出現在什么地方？--在名詞或代詞后。
掌握定語從句關系代詞和關系副詞的選用：
1）. 找出先行詞（即被定語從句所修飾的詞）
2）．將先行詞放入后面的定語從句中，看作何成分，指人還是指物；
3）．關系代詞（定語從句不完整時用）：Who(指人，作主語或賓語) whom (指人，作賓語) that which （指物，作主語或賓語，其中，that 不用于非限制性定語從句） whose (指人和物，作定語) ；
4）.關系副詞（定語從句完整時用）：when (作時間狀語)， where (作地點狀語)， why(作原因狀語)， how(作方式狀語)；(見上表)
二.which、as 可表示“這一點”，指代前面句子的內容；其中當謂語動詞為be 時或置于句首時只能用as；as 還有“正如”之意
三．Such … as；the same …as （定語從句“象(和)……樣的”as 在定語從句中作成分）與 such … that； （結果狀語從句“如此 … 以致, that 后句子完整）的區別
四．What 不用于定語從句。
五. 先行詞和關系詞二合一
1)Whoever spits in public will be punished here. (Whoever 可以用 anyone who 代替)
2)The parents will use what they have to send their son to technical school. (what 可以用all that代替)
六. what/whatever;that/what; who/whoever
1）what = the thing which；whatever = anything that
What you want has been sent here.
Whatever you want makes no difference to me.
2) who= the person that whoever= anyone who
（錯）Who breaks the law will be punished.
（錯）Whoever robbed the bank is not clear.
（對）Whoever breaks the law will be punished.
（對）Who robbed the bank is not clear.
七. that 和 what
當that引導定語從句時 ，通常用作關系代詞，而引導名詞性從句時，是個不充當任何成分的連接詞。賓語從句和表語從句中的that常可省略。What只能引導名詞性從句， 用作連接代詞，作從句的具體成分，且不能省略。
I think (that) you will like the stamps.
What we need is more practice.