① 關於英語中定語從句
假設語氣是什麼？虛擬語氣吧~~~
在"It is time(that)..."句型中，定語從句的謂語動詞常用虛擬語氣表示專將來，動詞形屬式用過去式或"should+動詞原形"，意思是「該干某事的時候了」。
如：
It's time we went (should go) to bed.我們該上床睡覺了。
It's (high) time we did our homework.我們該做作業了。
② 英語語法，定語從句
不是省略先行詞 而是省略關系代詞，關系代詞在從句中作間接賓語，一般應該用介詞to/for加關系代詞表達 即相當於間接賓語。如果關系代詞前面有介詞，則關系代詞不能省略，如果介詞在定從末尾，則關系代詞可以省略。
如he is the man to whom I gave the book.
He is the man (who/whom）i gave the book to。
③ 英語定語從句，語法
定語從句中，連接先行詞和定語的叫關系代詞或關系副詞。有一些情況下，關系代詞可以省略：
1、當關系代詞所代替的先行詞在定語從句中做賓語，關系詞可以省略。Whoistheman(that/who/whom)youweretalkingto? 剛才和你講話的人是誰？
2、當關系代詞that在定語從句中用作表語時，可以省略。
Chinaisnotthecountry(that)itwas. 中國已不是過去的中國了。
3、關系副詞when用於day,year,time少數詞後時可以省略（也可換成that）Thatwastheyear(that)Ifirstwentabroad. 就是那一年我第一次出國。
4、關系副詞where用於place, somewhere, anywhere, everywhere, nowhere少數詞後時可以省略(也可換成that)。
Thisistheplace(where)theymetyesterday. 這就是他們昨天碰頭的地方。
5、當關系代詞that在定語從句中用作賓語補足時，可以省略。
I』mnotthemadman(that)youthoughtme. 我並不是你所認為的那個瘋子。
6、關系副詞why通常只用於the reason後引導定語從句，且通常可換成that或for which，這些連接詞都可以省略。
That』s the reason (why, for which, that) he came. 這就是他來的原因。
Give me one reason (why) we should help you. 給我舉出一個我們應當幫助你的理由。
如有疑問，請追問，滿意，請採納，謝謝。
④ 英語語法定語從句
1.定語從句的定義：用作定語的從句叫定語從句。
2.先行詞：被定語從句所修飾的名詞或代詞。
3.定語從句的位置：緊跟先行詞(名詞或代詞)之後。
4.引導詞：引導定語從句的詞(包括關系代詞和關系副詞)。
﹙1﹚關系代詞：that/who/whom/which/as
﹙2﹚關系副詞：when/where/why
5.引導詞的位置：位於定語從句之前(先行詞之後)。【as除外】
6.引導詞的功能(作用)：
﹙1﹚連接先行詞和定語從句。
﹙2﹚在定語從句中充當一定的成分(關系代詞充當主語或賓語，關系副詞充當狀語)。
7.定語從句的類型：
﹙1﹚限定性定語從句(主句和定語從句之間無逗號)。
①
直接由引導詞引導定語從句
The
man
who
you』re
talking
to
is
my
friend.
②
由介詞+關系代詞(whom/which)引導
The
man
to
whom
you』re
talking
is
my
friend.
I
need
a
pen
with
which
I
can
write
a
letter.
=I
need
a
piece
of
paper
on
which
I
can
write
a
letter.
介詞的選用可根據從句中的相關片語確定，該介詞通常可以放在關系代詞之前，也可放在從句之尾。例如：
The
man
(who/whom/that)
I
talked
about
at
the
meeting
is
from
Beijing
University.
=The
man
about
whom
I
talked
at
the
meeting
is
from
Beijing
University.
The
palace
(which/that)
I
often
pay
a
visit
to
was
built
in
the
17th
century.
=The
palace
to
which
I
often
pay
a
visit
was
built
in
the
17th
century.
﹙2﹚非限定性定語從句(主句和定語從句之間用逗號隔開)。
①
直接由引導詞引導定語從句。
②
由介詞+關系代詞(whom/which)引導。
I
live
in
a
house
far
away
from
the
city，
in
front
of
which
is
a
big
tree.
There
is
an
apple
tree
standing
at
the
gate，
on
which
are
many
apples.
This
is
the
man
to
whom
I
gave
the
book.
③
由「代詞/名詞+of+whom/which」或「of
which/
whom
+名詞/代詞」(先行詞指
人用whom，指物用which)引導。One，
some，
any，
none，
all，
both，
several，
many，
most，
neither，
either等詞、數詞、分數或百分比與of
whom或of
which連用。
He
has
five
children，
two
of
whom
are
abroad.
(比較：He
has
five
children，
and
two
of
them
are
abroad.)
We
have
three
books，
none
of
which
is/are
interesting.
(比較：We
have
three
books，
but
none
of
them
is/are
interesting.)
除why和that不能引導非限定性定語從句外，其餘引導詞都可以，用法同限定性定語從句一樣。但要注意以下區別。
1.在形式上非限定性定語從句與主句有逗號隔開。
2.非限定性定語從句的作用：它只是補充說明先行詞的情況，翻譯時可譯成兩個句子。
The
engineer，
whose
leg
was
badly
hurt，
was
quickly
sent
to
hospital.
(那位工程師被很快送往醫院，其腿部受了重傷)
The
engineer
whose
leg
was
badly
hurt
was
quickly
sent
to
hospital.
(那位腿部受了重傷的工程師被很快送往醫院)
3.在非限定性定語從句中，任何引導詞都不能省略(包括引導詞在此定語從句中充當賓語在內)。指人做主語時只能用who，
做賓語時用whom；
指物做主語，賓語都用which；
關系副詞用when或where，也不能省略。
⑤ 關於英語語法——定語從句
一.定語從句及相關術語
1.定語從句：修飾一個名詞或代詞的從句稱為定語從句，一般緊跟在它所修飾的先行詞後面。
2.關系詞：引導定語從句的關聯詞成為關系詞
關系詞有關系代詞和關系副詞。關系代詞有that, which, who, whom, whose, as等；關系副詞有where, when,
why等。
關系詞常有3個作用：1，引導定語從句。2，代替先行詞。3，在定語從句中擔當一個成分。
二.關系代詞引導的定語從句
1.who指人，在從句中做主語
(1) The boys who are playing football are from Class One.
(2) Yesterday I helped an old man who lost his way.
2. whom指人，在定語從句中充當賓語，常可省略。
(1) Mr. Liu is the person (whom) you talked about on the bus.
(2) Mr. Ling is just the boy whom I want to see.
注意：關系代詞whom在口語和非正式語體中常用who代替，可省略。
(3) The man who/whom you met just now is my friend.
3. which指物，在定語從句中做主語或者賓語，做賓語時可省略
(1) Football is a game which is liked by most boys.
(2) This is the pen (which) he bought yesterday.
4. that指人時，相當於who或者whom；指物時，相當於which。在賓語從句中做主語或者賓語，做賓語時可省略。
(5) The number of the people that/who come to visit the city each year
rises one million.
(6) Where is the man that/whom I saw this morning?
5. whose通常指人，也可指物，在定語從句中做定語
(1) He has a friend whose father is a doctor.
(2) I once lived in a house whose roof has fallen in.
whose指物時，常用以下結構來代替
(3) The classroom whose door is broken will soon be repaired.
(4) The classroom the door of which is broken will soon be repaired.
(5) Do you like the book whose cover is yellow?
(6) Do you like the book the color of which is yellow?
三.介詞+關系代詞引導的定語從句
關系代詞在定語從句中做介詞賓語時，從句常由介詞+關系代詞引導
(1) The school (that/which) he once studied in is very famous.
(2) The school in which he once studied is very famous.
(3) Tomorrow I will bring here a magazine (that/which) you asked for.
(4) Tomorrow I will bring here a magazine for which you asked.
(5) We』ll go to hear the famous singer (whom/that/who) we have often
talked about.
(6) We』ll go to hear the famous singer about whom we have often talked.
注意：1. 含有介詞的動詞短語一般不拆開使用，如：look for, look after, take care of等
(1) This is the watch which/that I am looking for. (T)
(2) This is the watch for which I am looking. (F)
2. 若介詞放在關系代詞前，關系代詞指人時用whom，不可用who或者that；指物時用which，不能用that；關系代詞是所有格時用whose
(1) The man with whom you talked is my friend. (T)
(2) The man who/that you talked with is my friend. (F)
(3) The plane in which we flew to Canada is very comfortable. (T)
(4) The plane in that we flew in to Canada is very comfortable. (F)
3. 「介詞+關系代詞」前可有some, any, none, both, all, neither, most, each,
few等代詞或者數詞
(1) He loved his parents deeply, both of whom are very kind to him.
(2) In the basket there are quite many apples, some of which have gone
bad.
(3) There are forty students in our class in all, most of whom are from
big cities.
四．關系副詞引導的定語從句
1. when指時間，在定語從句中做時間狀語
(1) I still remember the day when I first came to the school.
(2) The time when we got together finally came.
2. where指地點，在定語從句中做地點狀語
(1) Shanghai is the city where I was born.
(2) The house where I lived ten years ago has been pulled down.
3. why指原因，在定語從句中做原因狀語
(1) Please tell me the reason why you missed the plane.
(2) I don』t know the reason why he looks unhappy today.
注意：關系副詞引導的從句可以由「介詞+關系代詞」引導的從句替換
(1) The reason why/ for which he refused the invitation is not clear,
(2) From the year when/in which he was going to school he began to know
what he wanted when he grew up.
(3) Great changes have taken place in the city in which./where I was
born.
五．限制性定語從句和非限制性定語從句
限制性定語從句 非限制性定語從句
形式上不用逗號和主句隔開用逗號和主句隔開
意義上是先行詞不可缺少的定語，不能刪除是對先行詞的補充說明，刪除後意思仍完整
譯法上翻譯成先行詞的定語，「…的…」通常翻譯成主句的並列句
關系詞的使用上A．做賓語時可省略 B。可用that
C．可用who代替whom A．不可省 B。不用that
C。不用who代替whom
限制性定語從句舉例：
(1) The teacher told me that Tom was the only person that I could
depend on.
(2) China is a country which has a long history.
非限制性定語從句舉例：
(1) His mother, who loves him very much, is strict with him.
(2) China, which was founded in 1949, is becoming more and more
powerful.
要注意區分以下幾個句子的不同
(1) His brother who is now a doctor always encourages him to go to
college.
他那當醫生的哥哥常鼓勵他要考上大學。（他還有其他的哥哥）
(2) His brother, who is now a doctor, always encourages him to go to
college.
他的哥哥是當醫生的，常鼓勵他要考上大學。（他只有一個哥哥）
難點分析
（一）限制性定語從句只能用that的幾種情況
1．當先行詞是anything, everything, nothing (something 除外), few, all, none,
little, some等代詞時，或者是由every, any, all, some, no, little, few, much等修飾時
(1) Have you taken down everything that Mr. Li has said?
(2) There seems to be nothing that seems impossible for him in the
world.
(3) All that can be done has been done.
(4) There is little that I can do for you.
注意：當先行詞指人時，偶爾也可以用who
(4) Any man that/.who has a sense of ty won』t do such a thing.
2. 當先行詞被序數詞修飾
(1) The first place that they visited in London was the Big Ben.
3. 當先行詞被形容詞最高級修飾時
(1) This is the best film that I have seen.
4. 當形容詞被the very, the only 修飾時
(1) This is the very dictionary that I want to buy,
(2) After the fire in his house, the old car is the only thing that he
owned.
當先行詞指人時，偶爾也可以用who
(3) Wang Hua is the only person in our school who will attend the
meeting/
5. 當先行詞前面有who, which等疑問代詞時
(1) Who is the man that is standing there?
(2) Which is the T-shirt that fits me most?
6. 當先行詞既有人，也有動物或者物體時
(1) Can you remember the scientist and his theory that we have learned?
（二）關系代詞as和which引導的定語從句
as和which引導非限制性定語從句，有相同之處也有不同之處。具體情況是：
1．As和which都可以在定語從句中做主語或者賓語，代表前面整個句子。
(1) He married her, as/which was natural.
(2) He was honest, as/which we can see.
2. as
引導非限制性定語從句，可放在主句之前，或者主句之後，甚至可以切割一個主句；which引導的非限制性定語從句只能放在主句之後。另外，as有「正如……，正像……」的意思
(1) As is known to all, China is a developing country.
(2) He is from the south, as we can see from his accent.
(3) John, as you know, is a famous writer.
(4) He has been to Paris more than several times, which I don』t
believe.
注意：當主句和從句存在邏輯上的因果關系時，常用which
(5) Tom was always late for school, which made his teacher angry.
3. 當先行次受such, the same修飾時，常用as
(1) I have never heard such a story as he tells.
(2) He is not such a fool as he looks.
(3) This is the same book as I lost last week.
注意：當先行次由the same修飾時，偶爾也用that引導定語從句，但是和由as所引導的定語從句意思不同
(4) She wore the same dress that she wore at Mary』s wedding.
她穿著她在MARY婚禮上穿過的一條裙子。
(5) She wore the same dress as her young sister wore. 她穿著和她妹妹所穿的一樣的裙子。
（三）以the way為先行詞的定語從句通常由in which, that引導，而且通常可以省略。
(1) The way in which/ that/./ he answered the question was surprising.
(四) but有時也可以做關系詞引導定語從句
(1) There are very few but understand his idea. ( but= who don』t )
(五) 區分定語從句和同位語從句
1．定語從句修飾先行詞，它和先行詞是修飾關系；同位語從句說明先行詞的具體內容，是補充說明的關系
(1) The plane that has just taken off is for London. 定語從句
(2) The fact that he has been dead is clear. 同位於從句
2．定語從句由關系代詞或者關系副詞引導，關系詞在句中充當成分，有時可以省略；同位語從句主要由that引導，在句中一般不做成分；句子也可以由when,
where, how, why, whether, what等詞引導，充當成分
(1) The news he told me is true.
(2) The news that he has just died is true.
(3) The problem that we are facing now is how we can collect so much
money. 定語
(4) The problem how we can collect so much money is difficult to solve.
3. 同位語從句和先行詞一般可以用be動詞發展成一個完整的句子，而定語從句不可以
(1) The idea that we could ask the teacher for advice is wonderful.
同位語
(2) The idea was that we could ask the teacher for advice.
(3) The fact that the earth moves around the earth is known to all.
(4) The fact is that the earth moves around the earth.
⑥ 英語定語從句的主要語法
關系詞的選用是重點
一. 選准關系代詞和關系副詞
在定語從句中，關系代詞或關系副詞都代替先行詞在從句中充當一定的成分，如果該從句中缺少主語、表語、賓語或定語，就要用關系代詞來連接從句；如果從句中缺少狀語，就得用關系副詞來連接從句。例如：
（1）I still remember the days which / that we spent together .
（2）I still remember the days when we worked together .
二. 了解僅用that 引導限制性定語從句的幾種情況
that 在限制性定語從句中既可指人又可指事或物。在下列情況下，只能用that 來引導定語從句：
1. 先行詞是all , much , few , little , everything , anything , nothing 等不定代詞時。例如：
Is there anything that you want to buy ?
2. 先行詞被all , few , little , much , every , some , no 等詞修飾或被the only , the very , the same , the last 等限定詞修飾時。例如：
These are all the pictures that I have seen .
This is the very dictionary that is of great help .
3. 先行詞既指人又指物時。例如：
My father and his teacher talked a lot about the things and the persons that they could remember .
4. 關系代詞在定語從句中作表語時。例如：
Our school is not the one that it used to be .
5. 先行詞被形容詞最高級或序數詞修飾時。例如：
This is the best English film that I have ever seen .
The first English novel that I read was A Tale of Two Cities .
6. 主句是who 或which 引導的特殊問句時。例如：
Who is the girl that is standing under the tree ?
Which is the machine that we used last Sunday ?
三. 把握「介詞＋關系代詞」結構中介詞的選用
介詞的選擇與主句中先行詞的搭配密切相關。例如：
That」s the reason for which he was late for school .
This is the book on which I spent 8 yuan .
注意：
1. 定語從句中謂語動詞是含有介詞的動詞短語時，介詞應放在動詞之後，不能拆開放在關系代詞前。例如：
This is the key which you are looking for .
This is the baby whom you will look after.
2. 該結構中，關系代詞指人時用whom，指物時用which .
四. 弄清as 和which 引導的非限制性定語從句指代整體時的區別
1. 位置上的區別：as 引導的非限制性定語從句的位置比較靈活，可以放在主句前，也可以放在主句後，還可插在主句的中間；而which 引導的非限制性定語從句只能放在主句之後。例如：
As is known to us all , the earth turns around the sun .
The earth , as is known to us all , turns around the sun .
The earth turns around the sun , as is known to us all .
The earth turns around the sun , which our parents once told us when we were very young .
2. 詞義與聯繫上的區別：as 引導的非限制性定語從句與主句之間有著較為密切的上下文聯系，as 本身含有「正如」之意；而which 引導的非限制性定語從句與主句之間在邏輯意義上近似並列句，which 本身表示「這」或「這一點」之意。例如：
Light travels faster than sound , as we all know .
Jack came late for school , which made his teacher angry .
五. 注意定語從句的主謂一致性
關系代詞在定語從句中作主語時，從句的謂語必須與先行詞保持人稱和數的一致。例如：
Tom is one of the boys who are from the USA.
Tom is the only one of the the boys who is from the USA.
六. 保持主句的完整性並避免從句成分的重疊
1. 在定語從句中，不管出現任何情況，主句的結構必須完整，即主句必須有主語和謂語，缺一不可，否則，整個主從復合句就無法成立。試比較：
（1）Is this factory _____________ we visited last week ?
（2）Is this the factory ____________ we visited last week ?
A. which B. where C. what D. the one
分析：
第一題缺少表語，只有填D項才能保持主句的完整性，而其他的選項均為干擾項。
第二題主句本身完整，應填的關系代詞在從句中作visited 的賓語，故應選A項。
2. 從定語從句中，關系代詞或關系副詞已經代替先行詞獨立地或與相應的介詞一起在定語從句中充當了一定的成分，因此在定語從句中就不能再出現與關系代（副）詞重疊的成分。例如：
錯句：Is this the train that they took it last Sunday ?
分析：該題中that 已經代替先行詞the train 在定語從句中充當及物動詞took 的賓語，故重疊出現的賓語it必須刪去
⑦ 英語定語從句語法。
就是用來形容抄名詞或者代詞
物用襲Which
人用Who、Whom、Whose
形容整個句子的時候用that（that有時可以省略）
語法就是一個句子里、你要兄容的名詞的後面緊跟一個句子、
從句用連接詞鏈接、句子的構造、順序不變
⑧ 求 關於 英語定語從句的語法[詳細的]
定語從句（Attributive Clauses）在句中做定語，修飾一個名詞或代詞，被修飾的名詞,片語或代詞即先行詞。定語從句通常出現在先行詞之後，由關系詞（關系代詞或關系副詞）引出。
位置：先行詞之後。
關系詞常有3個作用：
①連接作用，引導定語從句。
②代替先行詞。
③在定語從句中擔當一個成分。
關系代詞引導的定語從句舉例
關系代詞所代替的先行詞是人或物的名詞或代詞，並在從句中充當主語、賓語、定語等成分。關系代詞在定語從句中作主詞保持一致。
1,who, whom, that
這些詞代替指人，「whom」作賓語指人，「that」既可作主語又可作賓語（作賓語可以省略），可以指人也可以指物。在從句中所起作用如下：
（1）Is he the man who/that wants to see you? 他是那個想見你的男人嗎？（who/that在從句中作主語）
（2）He is the man whom/ that I saw yesterday. 他就是我昨天見的那個人。（whom/that在從句中作賓語）
（3）The man whom you spoke to just now is our English teacher. 你剛剛說話的那個男人是我們的英語老師。
2,Which 用來指人或物
(用作主語、賓語，作賓語時可以省略），例如：
（1）Prosperitywhich / that had neppearsin te. 農村出現了前所未有的繁榮。（which / that在從句中作主語）
（2）The package (which / that) you are carryingis about to come unwrapped.你拿那個包裹快要散開了。（which / that在從句中作賓語）
whose(只用作定語) 「whose」表示誰（可以為人也可以為物）的（東西） 例：
A child whose parents are dead is called an arphan.雙親都死了的孩子叫做孤兒。（「whose」表示那個孩子的雙親）
He lives in a room whose window faces south.他住的那個房子的窗戶是朝南的。（「whose」表示那個房子的窗戶）
關系代詞：在句中作主語、賓語或定語。
1. that既可代表事物也可代表人，「which」代表事物；它們在從句中作主語或賓語，「that」在從句中作賓語時常可省略關系詞，「which」在從省略。[eg：This is the book （which）you want.]
2. 不及物動詞+介詞」的介詞的賓語代詞「wh」放在它原來的位置。
3. 代表物時多這時的that常被省略；
c）被形容詞最高級修飾時；既有人又有物時；
e）整個句中前面已有「which」，「wh」行
關系副詞：在句中作狀語
關系副詞=介詞+關系代詞
why=for which
where=in/ at/ on which（介詞同先行詞搭配）
when=ring/ on/ in/…… which（介詞同先行詞搭配）
1. 「where」是關系代詞，當然也不用「that」引導。
By the time when you arrived in London, we had stayed there for two weeks. 到你到達倫敦的時候，我們在那裡已經待了兩個星期。
I still remember where I met her for the first time. 我仍然記得我第一次見到她。
Each time when he goes to business trip, he brings a lot of living necessities, such as towels, soap, toothbrush etc。 他每次出差都帶來了生活必需品，如毛巾，肥皂，牙刷等其他東西。
3. 當從句的邏輯主語是some, any, no, somebody, anybody, nobody, something, anything, everything或nothing時，常用「there is」開頭。
There is somebody here who wants to talk to you. 這里有人要和你說話。
分作進一步說明，通常是引導詞和先行詞之間用逗號隔開，將從句拿掉後其他部分仍可成立。
關系副詞的用法及說明
關系副詞why
關系副詞why主要用於修飾表示原因的名詞（主要是the reason），同時它在定語從句中用作原因狀語。如：
We don』t know the reason why he didn』t show up. 我們不知道他為什麼沒有來。
She didn』t tell me the reason why she refused the offer. 她沒跟我講她拒絕這項工作的原因。
與關系副詞when和where不同，why可以換成that或省略。如：
That』s one of the reasons (why, that) I asked you to come. 這就是我請你來的原因之一。
另外，與關系副詞when和where可以引導非限制性定語從句不一樣，why只能引導限制性定語從句，不能引導非限制性定語從句。如：
他失去工作的主要原因是他喝酒。
誤：The main reason, why he lost his job, was that he drank.
正：The main reason why he lost his job was that he drank.
關系副詞when
關系副詞when主要用於修飾表示時間的名詞，同時它在定語從句中用作時間狀語。如：
There comes a time when you have to make a choice. 你必須作出抉擇的時候到了。
Gone are the days when they could do what they liked. 他們為所欲為的日子一去不復返了。
We』ll put off the picnic until next week, when the weather may be better. 我們將把野餐推遲到下星期，那時天氣可能會好一點。
注意不要一見到先行詞為時間名詞，就以為一定要用關系副詞when來引導定語從句，同時還要看它在定語從句中充當什麼成分——如果在定語從句中用作時間狀語，就用when；如果在定語從句中不是用作時間狀語，而是用作主語或賓語，那就不能用when，而要用that, which等。如：
Don』t forget the time (that, which) I』ve told you. 不要忘記我告訴你的時間。
關系代詞that / which在定語從句中用作動詞told的賓語，正因為是用作賓語，所以也可以省略。
關系副詞where
關系副詞where主要用於修飾表示地點的名詞，同時它在定語從句中用作地點狀語。如：
This is the village where he was born. 這就是他出生的村子。
That』s the hotel where we were staying last summer. 這就是我們去年夏天住的旅館。
Barbary was working in Aubury, where she went daily in a bus. 巴巴拉在奧伯里工作，每天得坐公共汽車去上班。
與前面when的情況一樣，注意不要一見到先行詞為地點名詞，就以為一定要用關系副詞where來引導定語從句，同時還要看它在定語從句中充當什麼成分——如果在定語從句中用作地點狀語，就用where；如果在定語從句中不是用作地點狀語，而是用作主語或賓語，那就不能用where，而要用that, which等。如：
He works in a factory that [which] makes TV sets. 他在一家電視機廠工作。
關系代詞that / which在定語從句中用作主語。
另外注意，where有時還可用於抽象名詞後引導定語從句。如：
We have reached a point where a change is needed. 我們到了必須改一改的地步。
There are cases where the word 「mighty」is used as an adverb. 在一些情況下，mighty一詞可用作副詞。
He got into a situation where it is hard to decide what is right and wrong. 他陷入一種難以分辨是非的局面。
I don』t want a job where I』m chained to a desk all day. 我不想找一份整天坐辦公桌前的工作。
非限制性定語從句
意義：
非限制性定語從句起補充說明作用，缺少也不會影響全句的理解。在非限制性定語從句的前面往往有逗號隔開，如The house,which I bought last year,has a lovely garden.我去年買的的房子帶著個漂亮的花園。
This novel, which I have read three times, is very touching. 這本我已經讀過三遍的小說很感人。 3. 非限定性定語從句可將整個主句作為先行詞, 對其進行修飾, 這時從句謂語動詞要用第三人稱單數，例如：
He seems not to have grasped what I meant, which greatly upsets me.他似乎沒抓住我的意思，這使我心煩。
Liquid water changes to vapor, which is called evaporation. 液態水變為蒸汽，這就叫做蒸發。 4. 有時as也可用作關系代詞
5. 在非限定性定語從句中，不能用關在從句中做主語
（1）The boys who are playing football are from Class One. 在踢足球的男孩們是一班的。
（2）Yesterday I helped an old man who lost his way. 昨天，我幫助了一個迷路的老人。
whom指人
注意：關系代詞「whom」在口語和非正式語體中常用「who」代替，可省略。
如果在從句中做賓語，就用「whom」或「who」。
He is the man who has an English book. 他就是那個有英語書的男人。
You just met the person who was my friend. 你剛剛見到的那個人就是我的朋友。
which that 通常指人也可指物
在定語從句中做定語，表所有。
（1）He has a friend whose father is a doctor. 他有一個朋友的父親是醫生。
（2）I once lived in a house whose roof has fallen in.我曾經住在一座現在已經倒塌的房子中。 「whose」指物時通常以以下結構來代替：
（3）What is the color.Football is the game which is liked by most boys.
顏色是什麼。足球是大多數男孩都喜歡的游戲。
（4）This is the pen（which）he bought yesterday. 這是他昨天剛買的鋼筆。
that指人時，相當於「who」或者「whom」；指物時，相當於「which」當前頭有最高級序數詞「all」不定代詞時必須用「that」。
在定語從句中做主語、表語或者賓語，做賓語時可省略。
（5）The number of the people that/who come to visit the city each year rises one million. 每年來這座城市觀光的遊客數目上升了100萬。
（6）Where is the man this morning? 今天早上這個男人在哪？
when指時間，在定語從句中做時間狀語也可做連接詞用。
（1）(1) I still remember the day when I first came to the school. (2) The time when we got together finally came.
why指原因，在定語從句中做原因狀語。
（1）Please tell me the reason why you missed the plane.
（2）I don't know the reason why he lookswhen/in which he was going to school he began to know what he wanted when he grew up.
介詞和關系代詞
1）介詞後面的關系代詞不能省略。
2）「that」前「Do you」作介詞的賓語，且可以省略。例如：
（1）The school（that/which）he once studied in is very famous.「that/which」可以省略。
= The school I which hied is very famous.「which」不可省略。
（2）Tomorrow I will bring here 用，如：look for, look after, take care of等。
T This is the watch which/that I am looking for.（T=正確）
F This is the watch for which I am looking.（F=錯誤）
2. 若介詞放在關系代詞前，關系代詞指人時用「whom」，不可用「who」或者「that」；指物時用「which」，不能用「that」；關系代詞是所有格時用「whose」
（1）The man with whom you talked is my friend.（T）
The man famous.
（2）I bought many books yesterday, three of which are written by Lu Xun.
關系代詞
關系代詞（一般情況下）「that」可用在從句做主語，謂動詞的賓語，但是不能做介詞的賓語。 「which」指物，在從句句中作主語；
「whom」在從句中作賓語；
「why」在從句中修語，先行詞通常是「the reason」；
有時「why」也可用「for+which」代替。
例：A doctor who looks after people's health.
主語 謂語 先行詞 定語從句修飾先行詞
判斷介詞和關系代詞
方法一： 用關系代詞，還是關系副詞完全取決於從句中的謂語動詞。不及物動詞後面無賓語，就必須要求用關系副詞或者是介詞加關系代詞；而及物動詞後接賓語，則要求用關系代詞。例如：
This is the mountain village where I stayed last year.
判斷改錯:
（錯） This is the mountain village where I visited last year.
（錯） I will never forget the days when I spent in the countryside.
（對） This is the mountain village (which) I visited last year.
（對） I'll never forget the days (which) I spent in the countryside.
例. Is this the museum ____ the exhibition was held? A. whereB. thatC. on whichD. the one
解析：
主、謂、賓俱全，從句部分為句子的狀語表地點，既可用副詞where，又因 in the museum片語，可用介詞in + which 引導地點狀語。而此題中，介詞on 用的不對，所以選A。
關系詞的選擇依據在從句中所做的成分，先行詞在從句中做主、賓語時，選擇關系代詞（who, whom, that, which, whose）；
先行詞在從句中做狀語時，應選擇關系副詞（「where」地點狀語，「when」時間狀語，「why」原因狀語）。
先行詞和關系詞
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）
但這兩句句子已經不是定語從句了，是名詞性從句。因為定語從句一定要有先行詞，而名詞性從句沒有。將「Whoever」、「what」分別用「Anyone who」、「all that」代替後，才是定語從句，先行詞分別是「Anyone」、「all」。
an invitation from her boss, ___came as a surprise.
A. itB. thatC. whichD. he
答案C。
此為非限定性從句，不能用「that」修飾，而用「which」、「it」和「he」都使後句成為句子，兩個獨立的句子不能單以逗號連接。況且選「he」句意不通。
2）The weather turned out to be very good, ___ was more than we could expect.
A. whatB. whichC. thatD. it
答案B
英語語法上行不通。
3）It rained hard yesterday, ____ prevented me from going to the park.
A. thatB. whichC. asD. it
答案B
「as」和「which」在引導非限賓語。但不同之處主要有兩點：
（1）importance to me, as my own is.
在一定的語言環境里，有些名詞可以具有形容詞的性質。這些名詞主要是那些表示人的身份、職業、狀態的名詞。值得一提的是，在這些具有形容詞性質的名詞之後，引導定語從句的關系代詞不能用「who / whom」。
（2）動詞短語先行成分。
這種動詞短語既可是限定形式也可是非限定形式。如果是動態動詞短語，它們在從句中就一般有限定或非限定形式的替代動詞「do」和「as / which」一起代替。「do」可以出現，也可以不出現，但不能用其它動詞代替。
（3）句子作先行成分。
這句子可以是整個主句也可以只是主句中的一個從句。有時是連續幾個句子，有時甚至可以是一個完整的故事。
二、「as/which」特殊定語從句在句中的位置。
由於先行成分的構成成分」特殊定語從句在句中的位置有以下幾種情況：
1. 形容詞做先行成分時：形容質的which」特殊定語從句置於先行成分之後。
2. 動詞詞短語作先行成分時，「as / which」特殊定語從句置於先行成分之後。但是，當從句中含有表示主觀意志的插入成分時，「as」特殊。
3. 句子作先行成分時：「as」特殊定語從句的位置較靈活，可以置於先行成分之前、之中或之後。但如果先行成分是直接引語，「as」特殊定「s」特殊定語從句與否定詞的相對中則常用一些表示「合乎自然規律」、「眾所周知」或「經常發生」等意義的詞語，如natural, known to all, usual等。
3. 有無狀語意要是方式狀語意義，而「which」特殊定語從句則無狀語意義。「as」特殊定四、關系代詞「as」與「which」一詞。如：
Freddie, as might be expected, was attending the conference.
1). 「Which」作主語時，謂語動詞不限，主動被動皆可，只是謂語動詞為被動語態時助動詞「be」省略。
2). 「as」和「which」都可以在特殊定語從句中賓語。
3). 「as」和「which」在特殊從句中作補語。如：
We thought him a gentleman, as/which he could never be.
「as」特殊定語從句中可以主謂倒裝，「which」從句中則不能主謂倒裝。
如果先行成分不是主語補語或賓語補語，關系代詞用「which」而不用「as」。如：
He talked like a native, which/as he hardly was.
4."as"用法：
1)."as"引導限制性定語從句
a."such....as"
He is not such a fool as he looks.
I have never heard such a story as he tells.
b."the same ....as"
This is the same book as I lost last week.
(區分"the same...as"與"the same....that"："the same..as"指兩物相似;"the same...that"引導結果狀語從句)
c."as...as"
As many children as came were given some cakes.
2)."as"引導非限制性定語從句
常用句式:as is said above 綜上所述
as is known to all 眾所周知
as is often the case 通常如此
as is reported in the newspaper 如報紙所報道的
5. 「which」在特殊從定法
（1）不用that的情況
（a）在引導非限定性定語從句時。
（錯）The tree, which is four hundred years old, Is very famous here.
（b）介詞後不能用。
We depend on the land from which we get our food.
We depend on the land that/which we get our food from.
（2）只能用「that」作為定語如「last,just」修飾時，只用「that」。
（d）先行詞為序數詞、數容詞，又有物時。
（f）先行詞指物，在主句中作是「the way」或「the reason」時，「that」可作關系副詞，也可省略。
（h）主句的主語是疑問詞「who /which」時，避免重復要用「that」．
舉例：
Is this the book that you borrowed in the library?
這是你在圖書館借的書嗎？
Who that break the window should be punished．
誰打碎了窗戶。
All that is needed is a supply of oil.
everything that he had stolen to the police.
那賊最終把偷的全部東西交給了警察。
定語從句只能「that」引導的情況：
1、先行詞是最高級或被最高級修飾。
This is the most interesting book that l have ever read.
2、先行詞是序數詞或被序數詞修飾。
The second foreign country that l expect to visit is Greek.
3、先行詞是不定代詞時，如"all、few、little、much、anything、nothing、something"
This is the very good dictionary that I want to buy.
4.、先行詞既有人又有物時
Can you remember the scientist and his theory that we have learned?
5、先行詞被「only」、「the every」、「no」、「one of」等修飾
He is the only person that l want to talk to.
6、在以「which」、「who」、「whom」 引起的問句中，為避免重復，常用"that"
Who is the man that is standing there? Which is the T-shirt that fits me most?
7、「there be」句型中
8、先行詞在主句中作表語，或者關系代詞本身作從句的表語是宜用「that」
「that」在作賓語時可省略。
（五）區分定語從句和同位語從句
1、定語從句修飾先行詞，它和先行詞是修飾關系；
同位語從句說明先行詞的具體內容，是補充說明的關系。
（1）The planeis clear. 同位語從句
2、定語從句由關系代for advice.
（3）The fact that the moon moves around the earth is known to all.
（4）The fact is that the moon moves around the earth.
[定語從句]介詞+關系詞
1）介詞後面的關系副詞不能省略。
2）「that」前不能有介詞。
3）某些在從句中充當時間，地點或原因狀語的"介詞+關系詞"結構可以同關系副詞「when」和「where」互換。例如：
This is the house in which I lived two years ago. 這是我兩年前住過的房子。
This is the house where I lived two years ago.
Do you remember the day on which you joined our club？ 還記得你加入我們俱樂部的那一天嗎？ Do you remember the day when you joined our club？
⑨ 英語語法 關於定語從句
1）先行詞是不定代詞或者先行詞被不定代詞所修飾時，
關系代詞通常只用回that，
不用which.
2）先行詞被序數詞、答
形容詞最高級、
the
only，
the
very，
the
last等修飾時，
關系代詞通常只用that，
不用which.
3）先行詞既有人又有物時，
關系代詞只用that，
不用which
4）
關系代詞在限定性定語從句中作表語並帶有類比含義時，
通常只用that，
不用which.
5）
句中其他位置已出現which，
為避免重復，
不用which而用that引導限定性定語從句。
⑩ 英語語法 定語從句
這些你還是自己看抄書吧，平時認真聽課。這里和你講也會很復雜的
定語從句大類分成限制性和非限制性。
其中限制性定語從句中又有對事物的修飾，對人的修飾以及對人和物共同的修飾。
如果事物作為修行詞且沒有序數詞，最高級的情況下，用that
或
which
，如果做狀語，則要用when，where或in
which
如果先行詞是一個原因，用why或者for
which
如果先行詞是一個人，用who
如果先行詞是不定代詞，序數詞，最高級，關聯詞只能用that
如果先行詞在定語從句中做賓語成分，關聯詞可以不需要。