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定語從句用法（通用14篇）
定語從句是用來修飾一個名詞或代詞，進一步描述它的特征或性質的從句。這些從句通常由關系代詞或關系副詞引導，并且緊跟在被修飾的詞后面。以下是小編為大家整理的定語從句用法（通用14篇），希望能幫到大家。
定語從句用法 1
一.定語從句及相關術語
1.定語從句：修飾某一句中的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后面。被修飾的詞稱為先行詞。
2.關系詞：引導定語從句的關聯詞稱為關系詞
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，相當于who或者whom;指物時，相當于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
1. 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 talk-ed about.
(6) We’ll go to hear the famous singer about whom we have often talked.
2.關系代詞前的介詞的選擇
* 由先行詞的.習慣搭配或根據先行詞的需要。
(1) The speed at which light travels is 300,000 km per second. (at the speed of …以…速度)
(2) The reason for which he didn’t come to school was that he was ill. (for a certain reason 由于某種原因)
* 介詞可能是從句短語動詞的一個固定部分或固定搭配
(3) Don’t bring children to see the animals of which they are afraid. (be afraid of 害怕)
(4) This is the teacher from whom I borrowed the book. (borrow from…從…借入
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：1.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.
2.當先行詞為時間、地點、原因名詞時，如果在從句中不是作狀語時，不可用關系副詞引導。
(1)The reason (that/which) he gave for being late is that his mother was ill.
(2)They make me think of the happy days (that/which) we spent together.
(3)Is this factory the one (that/which) they visited the day before yester- day.
定語從句用法 2
定語從句用法講解
一、定語從句的識別
1、結構識別：名詞+連接詞+句子
【例句】Kevin gave us a wonderful training course, which left us a deep impression.
【解析】這個句子的前身應該是這樣的：Kevin gave us a wonderful training course. It left us a deep impression. it就是指代前面這個句子，這樣兩個句子就有了共有的名詞，連接兩個具有共同名詞的句子是定語從句的作用，就可以用which代替it，這樣就有了示例中的非限定性定語從句。
2、常用連接詞：
關系代詞：who, whom, which, that, as, whose
關系連詞：when, where, why, how
介詞+關系代詞：as和that以及who一般不能接到介詞后引導句子
二、定語從句的處理方法
1、按照定語的處理方法將定語從句前置，這種處理方式適用于比較短的和起修飾限定作用的定語從句。
2、在考研中大多數的定語從句起的作用是連接句子，因此我們通常把定語從句從整個句子中獨立拆分出來單獨成為一個句子，這種處理方法的關鍵是找到連接詞，拆分點就是連接詞。
對于“介詞+連接詞”引導的定語從句，拆分點就在介詞處。
【例句】There is something by virtue of which man is man.
【譯文】存在一種特性，人之所以為人就是由于這種特性。
【解析】這句話其實是由以下兩句話變來的：
1)There is something.
2)Man is man by virtue of this thing.這兩句話中有共有的名詞something和this thing，用which替換掉this thing再把of which提前，得到：There is something of which man is man by virtue
三、例句分析
【例句】Such large, impersonal manipulation of capital and industry greatly increased the numbers and importance of shareholders as a class, an element in national life representing irresponsible wealth detached from the land and the duties of the landowners; and almost equally detached from the responsible management of business.
【譯文】對資本和企業的這種大規模的.非個人操縱大大增加了股東作為一個階級的數量和重要性。這個階層作為國計民生的一部分，代表了非個人責任的財富與土地及土地所有者應盡義務的分離，而且也幾乎與責任管理相分離。
【解析】句子的主干為：Such large, impersonal manipulation of capital and industry greatly increased…shareholders as a class, (which was) an element…這句話的難點還在于其主語和賓語都有較長的短語和of結構限定，并且分句是由兩個and相連的3個部分組成的。
分句an element…landowners又帶有兩個定語從句，一個是(which was)representing…，另一個是(which was)detached…。可見，定語從句的難點在于經常省略“引導詞+be”的結構，從而在理解上容易和分詞結構相混淆。實際上定語從句并不符合漢語的使用習慣。所以翻譯時遇上定語從句，一定不要機械地按照原來的順序生搬硬套。像這樣分句較長的情況，把主句和分句拆為兩句是比較好的方法。所以這里從“這個階層”開始另起一句。
定語從句用法 3
定語從句用法的詳解
一、定語從句的有關概念
所謂定語從句，就是在復合句中起定語作用以修飾主句中的名詞或代詞的從句。學習定語從句，首先要弄清兩個重要概念——先行詞和關系詞。
先行詞是我們漢語中從來沒有聽過的一個新概念，它其實指的就是被定語從句所修飾的詞。由于定語從句修飾名詞或代詞時，定語從句通常是后置的，所以人們就將放在定語從句前被定語從句修飾的名詞或代詞叫先行詞。
那什么是關系詞呢？其實它就是用于引導定語從句的引導詞。事實上，英語中的各類從句，不管性質如何，它們都需要有一個詞來“引導”，正如人們給引導狀語從句的詞語取了個名字叫從屬連詞一樣，人們也給引導定語從句的詞語取了個名字，叫它關系詞，因為它通常被放在先行詞和定語從句之間起連接作用，以表明兩者之間的修飾關系，同時它還在定語從句中充當一定的句子成分。
二、定語從句中關系詞與所修飾先行詞的關系
為了更好地理解定語從句，我們還有必要研究一下關系詞與先行詞之間的關系。但在研究這種關系之前，我們先來看看關系詞有哪些。
根據關系詞在定語從句中的作用，我們可以將關系詞分為關系代詞和關系副詞兩種。所謂關系代詞就是指起代詞作用的關系詞，它們在引導定語從句的同時，還在定語從句中充當主語、賓語、賓語等，英語中比較常用的關系代詞有that, which, who, whom, whose等。
類似地，關系副詞就是指起副詞作用的關系詞，它們在引導定語從句的同時，還在定語從句中充當狀語等，英語中比較常用的關系副詞只有三個，即when, where和why。
許多初學定語從句的人弄不清關系詞與先行詞之間到底是什么關系。其實啊，關系詞與先行詞之間的關系很簡單，簡單得可以劃一個等號。因為，關系詞的含義在本質上等價于先行詞，它與先行詞指的就是同一個人或同一個事物。為便于理解，下面我們來看幾個例子吧。
I know the man who lives next door.我認識住在隔壁的那個人。
這是一個含有定語從句的復合句。句中的the man為先行詞，who lives next door為修飾the man的定語從句；在定語從句中，who是關系詞，它在定語從句中用作主語，從意義上說，它在此所表示的意思與先行詞the man等價，換句話說，上面這個句子與下面這個句子等價：I know the man. He lives next door.我認識這個人，它就住在隔壁。
She will never forget the day when she got married.她永遠不會忘記她結婚的這一天。
句中的the day為先行詞，when she got married為修飾the day的定語從句；在定語從句中，when是關系詞，它在定語從句中用作狀語，從意義上說，它在此與“介詞+先行詞”所表示的意思等價，也就是說上面的句子與下面這個句子等價：She will never forget the day. On that day she got married.她永遠不會忘記這一天，在這一天她結婚了。
三、定語從句的翻譯
許多英語初學者往往弄不明白為什么引導定語從句的關系詞which不能譯為“哪一個”，who不能譯為“誰”，when不能譯為“什么時候”，where不能譯為“什么地方”，等等。
首先，我們必須要明白一點，那就是引導定語從句的which, who, when, where, why等是關系詞（關系代詞或關系副詞），而不是疑問詞，所以不能按疑問詞的意思來理解。
前面我們講到，英語中的定語從句總是后置的，即要放在被修飾名詞或代詞之后；但在漢語中，定語通常是前置的，也就是說定語要放在被修飾名詞的前面，并通常表現為“……的”這樣的形式。當我們翻譯英語中定語從句的時候，一般可以按漢語習慣，將定語從句翻譯在被修飾的名詞或代詞之前，而其中的關系詞一般就是譯成漢語中的“……的”。如：
He showed me the article that he had written.他把他寫的文章拿給我看。
句中的that he had written為修飾名詞the article的定語從句，翻譯時就可譯為“他寫的文章”，其中的關系代詞that在此譯成了“的”字。
She was not in the train which arrived just now.她不在剛到的那列火車上。
句中的which arrived just now為修飾名詞the train的定語從句，翻譯時就可譯為“剛才到的那列火車”，其中的關系代詞which在此也譯成了“的”字。
Sunday is the day when very few people go to work.星期日是沒什么人上班的日子。
句中的when very few people go to work為修飾名詞the day的定語從句，翻譯時就可譯為“沒什么人去上班的日子”，其中的.關系副詞when在此也譯成了“的”字。
That’s the hotel where we were staying last summer.這就是我們去年夏天住的旅館。
句中的when very few people go to work為修飾名詞the day的定語從句，翻譯時就可譯為“沒什么人去上班的日子”，其中的關系副詞when在此也譯成了“的”字。
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。
句中的why we should help you為修飾名詞one reason的定語從句，翻譯時就可譯為“我們應當幫助你的理由”，其中的關系副詞why在此也譯成了“的”字。
當然，我們上面介紹的是翻譯定語從句最簡單同時也是最基本的方法，由于英語句子千變萬化，定語從句的表現形式也靈活多樣，有些含有定語從句的句子可能用此方法翻譯會顯得別扭，但只要掌握了這個基本的方法，再加上適當的變通，翻譯定語從句也就不難了。
四、定語從句中關系代詞的省略
省略關系代詞最典型的情形就是當關系代詞在定語從句中用作賓語的時候。在定語從句中能夠用作賓語的關系代詞有that, which, who, whom。如：
Those books (that) you lent me were very useful.你借給我的那些書很有用。
句中的(that) you lent me為修飾those books的定語從句，引導定語從句的關系代詞that在定語從句中用作動詞lent的賓語，故可以省略。
I wore the necklace (which) my mother had left me.我戴著我媽留給我的項鏈。
句中的(which) my mother had left me為修飾the necklace的定語從句，引導定語從句的關系代詞which在定語從句中用作動詞left的賓語，故可以省略。
Do you still remember the boy (who, whom) I was going out with?你還記得那個跟我約會的小伙子嗎?
句中的(who, whom) I was going out with為修飾the boy的定語從句，引導定語從句的關系代詞who / whom在定語從句中用作句尾介詞with的賓語，故可以省略。
注意：我們說的關系代詞的省略只限于限制性定語從句，在非限制性定語從句中，即使關系代詞用作賓語也不能省略。另外，當關系代詞直接用作介詞后作賓語時，此時也不能省略。如：
I wanted to find someone with whom I could discuss books and music.我想找到一個可以和我談書和音樂的人。
此句中的關系代詞which雖然也是用作賓語，但不能省略，因為它是直接跟在介詞with后面作賓語。但是，如果將此句改寫一下，將介詞with置于句末，則可以將關系代詞whom省略。如：
I wanted to find someone (whom) I could discuss books and music with.我想找到一個可以和我談書和音樂的人。
定語從句用法 4
一、as引導定語從句
as引導定語從句時，既可以引導限定性定語從句，又可以引導非限定性定語從句。區分as引導定語從句和其它從句的關鍵特征是：as引導定語從句時在從句中做成分，通常做主語或賓語。
1、as引導限定性定語從句
如從句所修飾的名詞前有such、the same、as出現，后面的定語從句將由as引導，形成such...as，the same...as，as…as這樣的固定結構，譯為“和……一樣”。
例1：I never heard such stories as he told.
我從未聽過他所講的那樣的故事。
例2：He’ll repeat such questions as are discussed in the book.
他將重復書中討論過的問題。
例3：They made the same mistake as others would have made on such an occasion.
他們犯了和其他人在這種場合下會犯的同樣錯誤as用法詳解as用法詳解。
2、as引導非限定性定語從句
as引導非限定性定語從句，往往指代一整句話，通常表示“正如”的意思。as引導的非限制性定語從句位置相對比較靈活，可以位于先行詞之前、之后或中間。
例：As is known to everybody, the moon travels round the earth.
眾所周知，月亮繞著地球轉。
二、as引導時間狀語從句
as引導時間狀語從句多用于口語，強調“同一時間”或“一先一后”，有時還有“隨著”的'含義。
例1：As I was going out, it began to rain.
當我出門時，開始下雨了。(as強調兩個動作緊接著發生，不強調下雨的特定時間。)
例2：As time goes on, he will understand what I said.
隨著時間的推移，他會理解我所講的話。
三、as引導原因狀語從句
as表示“因為”，與because相比，較口語化，所表達的原因語氣較弱，所表的原因比較明顯，或是已知的事實。
例1：As the weather is so bad, we have to delay our journey.
因為天氣太糟糕，我們不得不推遲旅行。
例2：Any new source of energy will be very welcome, as there is already a shortage of petroleum.
任何新型能源都將大受歡迎，因為石油已經出現短缺。
四、as引導方式狀語從句
as表示“按照”，“以……方式”，“像……一樣”，“正如”。
例：Do as the Romans do when in Rome. 入鄉隨俗
注：as在引導方式狀語從句時，還常出現在一個固定的類比結構中：(just) as …, so…。這一句型表示類比，基本含義是“正如……，所以……”。
例：Just as virtue is its own reward, so is vice its own punishment.
善有善報，惡有惡報。
五、as引導讓步狀語從句
as可以表示“盡管”，“雖然”，引導讓步狀語從句，但必須構成倒裝。讓步狀語從句倒裝規則有兩類：
1、形容詞/副詞/分詞/名詞(無冠詞)/介詞短語等+as+主語+謂語動詞，主句。
例1：Much as I like you, I couldn’t live with you.
我盡管很喜歡你，卻不能和你在一起生活。
例2：Child as he is, he knows to help others.
盡管他是個孩子，他懂得幫助別人。
2、動詞原形+as+主語+助動詞(may/might, will/would, can/could, do/does/did)，主句as用法詳解考研英語。
例：Try as we may, we cannot sense directly the television signal sent out from the broadcast station.
盡管我們費了很大的勁，也無法直接覺察發射臺發出的電視信號
六、as引導比較狀語從句
as引導比較狀語從句，其基本結構是as…as。前一個as是副詞，后一個as是比較狀語從句的連詞。否定結構為not so much … as …。
例1：Small as it is, the ant is as much a creature as are all other animals on the earth.
盡管螞蟻很小，但是它同地球上的任何其他動物一樣，也是一種動物。
例2：It was not so much the many blows he received as the lack of fighting spirit that led to his losing the game.
與其說是他受到了許多打擊，還不如說是缺乏斗志使他輸掉了比賽。
定語從句用法 5
從句中that的用法
一、that引導名詞性從句時(即主語從句、賓語從句、表語從句、同位語從句),在從句中無具體含義,只起連接作用,而且在從句中也不作任何句子成分.它所引導的從句的句子結構和意義是完整的,而且從句一般是陳述一個事實.
例如:
①Thatshe was able to come made us very happy.
她能來使我們很高興.
②The newsthatour team has won the match is true.
我們隊贏了這場比賽的消息是真的
③The reason he didnt come wasthathe was ill.
他沒來的原因是他病了.
當that引導的主語從句或賓語從句太長時,常用it作形式主語或賓語而把that從句放在后面.如:
①It is well—knownthatthe earth is round.
眾所周知,地球是圓的
②We find it necessarythatwe practise spoken English every day.
我們發現每天練習英語口語很有必要.
注意：
that引導的.主語從句,表語從句以及同位語中,that不能省略.that引導的賓語從句,一般可以省去that,但在下面情況中不能省略——
1.在suggest,order等表示命令、請求、建議等動詞后的賓語從句中,不能省;
2.由and或but所連接的兩個引導的賓語從句時,第一個從句中的that可以省,第二個從句中的that不能省;
3.that引導的賓語從句,如果從句中還有其他狀語從句,引導賓語從句的that不能省略.
Tell himthatif he is at home,Ill call to see him.
二,that引導定語從句要注意以下幾點:
1.定語從句中缺主語,修飾人時用who /that,修飾物時用which /that引導.如:
Is this the factory which /thatmakes TV sets
The man who /thatvisited our school is from Australia.
2.從句中缺賓語,修飾人時用 who /whom /that或省略引導詞;修飾物時用which /that或省略引導詞.如:
Gone are the days which /thatwe spent together in the village.
He is the man who /whom /thatI think to be worthy of our praise.
3.用that不用which的七種情況:
①先行詞前有形容詞最高級或序數詞修飾時,用that不用which引導.如:
This is the best placethatI have ever visited.
②先行詞為little,much,all,none,few,(the)one,something,everything,nothing,anything等不定代詞時,用that引導.如:
There is nothing in the worldthatcan frighten him.
③先行詞既有指人的名詞又有指物的名詞時,用that引導.如:
He told us about the people and the citiesthathe had visited.
④先行詞前有any,all,no,few,every,some,little,much,(the)very,(the)only,(the)last等詞修飾時,用that引導.如:
This is the very coatthatI need.
⑤先行詞為which時,為了避免重復,用that引導.如:
Which is the bookthatyou bought yesterday
⑥先行詞在從句中作表語時,常用that引導.如:
Shanghai is no longer the citythatit used to be in the 1930s.
⑦當主句是There be...句型時,用that引導.
There are two tickets for the filmthatare for you two.
定語從句用法 6
when引導
關系副詞when在非限制性定語從句中作時間狀語，指代主句中表示時間的詞語。
如：He will put off the picnic until May 1st, when he will be free.
他將把郊游推遲到5月1號，那時他將有空。
where引導
副詞where在非限制性定語從句中作地點狀語，指代主句中表示地點的詞語。
如：They went to London，where they lived for six months.
他們去了倫敦，在那兒呆了六個月的時間。
as引導
as引出非限定性定語從句時，代替整個主句，對其進行說明但通常用于像as we all know, as it is known, as is known to all, as it is, as is said above, as always mentioned above, as is usual, as is often the case, as is reported in the newspaper等句式中。as在非限定性定語從句中作主語、表語或賓語，且引出的從句位置比較靈活，可位于句首或句末，也可置于主句中間。通常均由逗號將其與主句隔開。as有“正如……， 就像……”之意。
如：As is known to the United States, Mark Twain is a great American writer.
美國人都知道，馬克·吐溫是一位偉大的美國作家。（as在從句中作主語）
He forgot to bring his pen with him, as was often the case.
他忘了帶筆，這是常事。（as在從句中作主語）
He is absorbed in work, as he often was.
他正在全神貫注地工作，他過去經常這樣。（as在從句中作表語）
As we all know, the earth is round.
眾所周知，地球是圓的。（as在從句中作賓語）
The two brothers were satisfied with this decision，as was agreed beforehand.
兩兄弟對此決定都滿意，這項決定在事前都已得到他們的同意。(as在從句中作主語)
Taiwan is，as you know，an inseparable part of China.
你知道，臺灣是中國不可分割的'一部分。(as在從句中作賓語)
“介詞+關系代詞”引導非限制性定語從句：在介詞后引導非限制性定語從句。
難：句意相同
as it is known to all (that...) (as 做狀語從句連詞，是狀語從句, 可以加that)
與 as is known to all (as做主語，是定語從句)
與 it is known to all that... (主語從句，it是形式主語)
即：As is widely known, the moon is closer to the us than the sun.(定從)
= That the moon is closer to the us than the sun is widely known.(主從)
= It is widely known that the moon is closer to the us than the sun.(主從)
As it is known to everyone, I thought you knew about it too.(狀從)[1]
關系代詞which有時并不代表主句中某一確定的詞，而是概括整個主句的意思。介詞的選擇取決于它與先行詞的搭配或與從句中謂語動詞的搭配。
They were short of sticks to make frames for the climbing vines，without which the yield would be halved.
他們缺搭葡萄架的桿兒，沒有它們產量會減少一半。
They thanked Tom，without whose support they would not have succeeded.
他們很感激Tom，沒有他的支持他們是不會成功的。
特殊結構
“名詞/代詞+of+which / whom”
It now has 20，000 hectares of land，more than two-thirds of which are under cultivation.
現在它擁有兩萬公頃土地，其中三分之二之多已經耕種。
Light is the fast thing in the world, the speed of which is 300000 kilometer per second.
光是世界上最快的東西，它的速度是每秒30萬千米。
There are 30 chairs in the small hall, most of which are new.
大廳里有三十把椅子，絕大部分是新的。
The textile mill has over 8，000 workers and staff，eighty per cent of whom are women.
這家紡織廠有8千多職工，女職工占百分之八十。
定語從句用法 7
一、as引導定語從句與其它詞連用
A．用于the same．．．as．．．結構中
This is the same sickle as I lost yesterday．這把鐮刀和我昨天丟的那把一樣。
We drove out of the town by the same road as we had entered by．我們沿著進城的同一道路開車出城。
This is the same material as is used in building the bridge．這和建那座橋所用的材料一樣。
注意：在這一結構中，as有時可以由that代替。例如：
I live in the same district as ／that he lives in．我和他住在同一區。
但兩者亦有區別：
1．當定語從句省略謂語部分時，要用as。例如：
She uses the same scent as you（do）／that you do．她用的香水和你的一樣。
This book of his is the same as yours．他的這本書和你的那本一樣。
2．在容易引起歧義時，慎用as和that。例如：
This is the same knife as I lost last week．
（一般理解為：這把刀和我上周丟的那把相似。也可理解為：這是我上周丟的那把刀。）
This is the same knife that I lost last week．這是我上周丟的那把刀。
3．that在現代英語中可作關系副詞，而as則不可。例如：
I live in the same district that he lives．（不可用as。）
B．用于such．．．as．．．結構中
I never heard such stories as he tells．我從未聽過像他講的那種故事。
He was in such a fury as Ive never seen．他怒氣之大，我從沒見過。
Such women as knew Tom thought he was charming．認識湯姆的女人都認為他很有魅力。
注：有時such和as連在一起用。例如：
We had hoped to give you a chance such as nobody else ever had．我們本希望給你一次別人不曾有過的機會。
We are living in a new era such as has never existed before．我們生活在前所未有的新時代。
C．用于“so＋adj．＋a（n）＋n．（單數）＋as結構中
We witnessed so great a parade as nobody ever dreamt of in preliberation days．我們見到在解放前沒有人曾經夢想過的一次盛大的。
Im not so strong a man as I was．我已不像從前一樣健康了。
Hes never written again so good a book as his first one．他再也沒寫出像他的第一部那么好的書。
D．用于“as＋adj．＋n．＋as比較結構中
He is as learned a professor as works in the uni- versity．他是在這所大學工作的教授中最有學問的一個。
Some people have no doubt that their cat understands as many words as does a dog．許多人相信他們的貓跟狗懂的話一樣多。
They are as fine women as ever walked．她們可以與任何卓越的女性媲美。
注：as．．．as．．．后面加上ever以加強語氣，表示“不亞于任何……”，“不弱于……”，有最高級的意味。又如：
He is as brave a man as ever lived．他是世界上最勇敢的人。
二、as單獨引導定語從句
A．as單獨引導定語從句時，先行詞可以是一個詞，但更為常見的'是：它的先行詞是整個主句，有時也可以是一個短語。例如：
The two brothers were satisfied with this decision，as was agreed to beforehand兩兄弟對此決定都很滿意，這項決定事前已得到他們的同意。（先行詞是decision）
She is late，as is often the case．她遲到了，這是經常的事。（先行詞是整個主句）
He married her，as was natural．他和她結婚了，這是很自然的。（先行詞是整個主句）
To shut your eyes to facts，as many of you do，is foolish．視而不見———你們好多人都是如此———是愚蠢的。（先行詞是整個不定式短語）
B．as與which的區別
三、as引導定語從句的用法比較
1.as作為關系代詞可以引導限制性定語從句， 主要用于such...as，the same...as，so...as，as...as等結構中。例如：
（15）Let’s deal with such problems as concern us.
（16）The purpose of the conductor is to transmit the electrical energy with as little loss as is practicable.
（17）There are so many tickets available as are asked for.
（18）She wears the same watch as I do.（同一類）
（19）This is the same watch that I lost yesterday.（同一個）
在（15）句中，as指代such修飾的名詞“problem”，并在從句中作主語成分；（16）句中，第二個as指代第一個as所修飾的“little loss”; （17） 句中as 指代so 修飾的名詞“tickets”; 在（18） 句中，as 指代“the same” 修飾的名詞“clothes”， 在從句中作賓語； 此情況下不能用that和which來代替as引導定語從句。
比 較：在（18）句中，as指代的先行詞表同一類，強調種類一樣。而在（19）中that指代的先行詞雖然也被“the same”修飾，但是此時先行詞表示同一個。
2.as和which引導非限制性定語從句比較。
as和which都可以引導非限制性定語從句，代替整個句子。但是具體使用方法是有區別的，請看下面的例句比較：
（20）As we known，Yao Ming is the most famous basketballplayer in China.
（21）The number of the people，as we had expected，was overthree thousand.
（22）The sun gives off light and warmth，which makes it possiblefor living creatures to grow.
（23）She is very beautiful，which makes others jealous.
（24）She is very kind to the children，which her husband seldomwas.
（25）He became a teacher，which I was not.
在（20）句中as放在了句首，所指代的內容就是后面的一句話“Yao Ming is the most famous basketball player in China”；（21）句as放在了句中，同樣指代的是一句話“The numberof the people was over three thousand”。從這兩個例句中我們發現as引導的從句和主句在內容上表示一致， 或者說從句的內容是順著主句的意思說下來的，有“就像”、“正如”之意。再看一下（22）句和（23）句，which的位置放在了句中，并且which引導的非限制定語從句是主句造成的一種結果。比如我們在翻譯（22）句時可以這樣理解：太陽釋放出光和熱，這使生物生長成為可能；當然（23）句我們也可以這樣翻譯：她很漂亮，這使其他人和嫉妒。從（24）句和（25）句我們還可以看到which引導非限制性定語從句的另一種用法，即which引導的非限制定語從句與主句內容不一致， 或起對立、否定關系。
四、as引導狀語從句的用法比較
1.as，when和while作為連詞引導時間狀語從句的比較。
若主、從句表示兩個同時進行的持續性動作，且強調主句表示的動作延續到從句所指的整個時間， 通常要用while。但是，若主、從句表示的兩個同時進行的動作含有“一邊……一邊”的意思，通常要用as。例如：
（26）Don’t talk while you’re eating.
（27）I kept silent while she was reading.
（28）She sang as she went along.
若從句是一個短暫性動作，而主句是一個持續性動作，一般用when。如果主、從句表示的是兩個同時（或幾乎同時）發生的短暫性動作，一般要用as。例如：
（29）When he came in，I was watching TV.
（30）It was raining hard when he arrived.
（31）I had guessed it just as you opened your mouth.
若要表示兩個正在發展變化的情況， 相當于漢語的“隨著”，一般用as。表示“每當……的時候”（暗示一種規律性），一般要用when。例如：
（32）Situations are getting better and better as time goes on.
（33）As it grew darker，it became colder.
（34）It’s warm when sun shines.
（35）He smiled when I praised him.
2.as，though 和although 作為連詞引導讓步狀語從句的對比。
as引導讓步從句時，句子必須倒裝。常把被強調的作表語的形容詞、名詞及作狀語的副詞放句首，有時甚至把謂語動詞放句首。though引導讓步狀語時，句子可以倒裝（倒裝方式和as一樣）也可以不倒裝。although引導讓步狀語時，只能用正常語序，不能倒裝。下面我們看一下例句（36）—（39）：
（36）Poor as/though they are，they are very ambitious.
（37）Child as/though he is，his behavior seems mature.
（38）Hard as/though he worked，he didn’t pass the exam.
（39）Try hard as/though he will，he is not successful.
3.as，because，since 和for 作為連詞引導原因狀語從句比較。
because引導原因狀語從句時語氣最強， 常表示必然的因果關系，從句是全句的重心，它引導的從句一般放在主句的后面， 并且回答以why引起的特殊疑問句；as只說明一般的因果關系，語氣比because弱，說明比較明顯的原因，它引導的從句通常放在句首，常意為“由于”；since意為“既然”，表示對方已經知曉，無需加以說明的原因或事實（有時為天經地義的事實或格言、諺語等），語氣比because稍弱，全句重點落在主句上；for是并列連詞，它的語氣最弱，常用來補充說明理由或提供一種解釋，一般放在句中，強調“理由”。下面我們看一下例句再一次進行比較。
（40）He is absent today because he is ill.
（41）As everyone has arrived，we can set off now.
（42）I’ll do it for you since you are busy.
（43）We must leave now，for the film begins at seven.
4.as引導的方式狀語從句用法。
as，（just） as...so...引導的方式狀語從句通常位于主句后，但在（just） as...so...結構中位于句首，這時as從句帶有比喻的含義，意思是“正如”、“就像”，多用于正式文體，例如：
（44）I shall do the exercises as you have been taught.
（45）As water is to fish，so air is to man.
（46）Just as we sweep our rooms，so we should sweep old ideas from our heads.
總之， 社會和英語語言的不斷發展給英語語法的歸納和研究帶來了很大的挑戰，也給語言學習者帶來了很多困難，但不管怎樣，只要我們在學習過程中不斷探索、勇往直前，一定能找到其中的規律， 幫助英語學習者消除英語學習中的重重障礙。
定語從句用法 8
WHOSE也可以引導定語從句，它相當于前面說的關系代詞的所有格形式。
例：She has an uncle . His name is Peter.
=She has an uncle whose name is Peter.
I like that house . Its location is good to me.
=I like that house whose location is good to me.
"WHOSE"引導定語從句的三原則:
a. whose 前要有先行詞
b. whose 后的名詞要做定語從句的主語或賓語
c. 否則whose前應有介詞，且該介詞也可移至定語從句的句尾
以上可知whose引導定語從句的用法和其他關系代詞的用法相似。
例：I hate John,whose words are seldom true.(本句中，whose words 前有先行詞John，且本身做定語從句的主語)
I hate John,whose words I have no trust.(錯) (本句雖有先行詞,但whose words 無法直接做trust的賓語，所以要稍加改正)
改正:I hate John,whose words I seldom trust in.(對)
附一：關系代詞引導的定語從句
關系代詞所代替的`先行詞是人或物的名詞或代詞，并在句中充當主語、賓語、定語等成分。關系代詞在定語從句中作主語時，從句謂語動詞的人稱和數要和先行詞保持一致。
1、who指人，在從句中做主語
The boys who are playing football are from Class One.
2、whom指人，在定語從句中充當賓語，常可省略。
Mr. Liu is the person (whom)you talked about on the bus.
【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。
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
Football is a game which is liked by most boys.
4、that指人時，相當于who或者whom；指物時，相當于which。在定語從句中做主語或者賓語，做賓語時可省略。
The number of the people that/who come to visit the city each year rises one million.
5、whose通常指人，也可指物，在定語從句中做定語
He has a friend whose father is a doctor.
whose指物時，常用以下結構來代替：
The classroom whose door is broken will soon be repaired.
=The classroom of which the door is broken will soon be repaired.
Do you like the book whose cover is yellow?
=Do you like the book the color of which is yellow?
（注意：the + 名詞 + of which/whom常考！）
附二：介詞+關系代詞whom/which引導的定語從句（重點）
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：
The school (that/which) he once studied in is very famous.
=The school in which he once studied is very famous.
【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 lookingfor.(T)
（2）This is the watch for which I amlooking. (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、“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，構成some of which/whom等類似結構引導的定語從句。(重點：常考！)
（1）He loved his parents deeply, of whom both 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.
在特定語境中，可以用“介詞+ whose/where”引導定語從句
The boss in whose department Ms King once worked is a kind man.
定語從句用法 9
1、引導限制性定語從句。在主句中常有the same, so或such與as相呼應, as在定語從句中可作主語、賓語、主語補足語等。as引出的定語從句帶有比較意義，從句常常只寫出比較部分，但as本身不可省略。例如：
He used such expressions as he could find in the texts. 他使用在課文中可以找到的那些詞語。 They stayed for the night in the same room as they had once rented.他們在他們曾租用過的同一房間過夜。
注意：在the same…后也可用that引導定語從句，但含義有所不同。that引出的從句，指的是與先行詞同一的事物，而as引導的從句指的是與先行詞同類的事物。例如： This is the same bag as I lost yesterday.這個包和我昨天丟失的包的樣子是同樣的。 This is the same bag that I lost yesterday.這就是我昨天丟失的那個包。
2、引導非限制性定語從句。帶主句的全部或部分內容。常譯為“正如-------”“就像------”等，定語從句可以置于主句句首、句中或句末。as后常接expect, know, report, say, see等動詞的主、被動語態。例如：
As is known to everybody, the moon travels round the earth once every month.正如大家所知道的'那樣，月球每月繞著地球轉一圈。
He wasn’t unconscious, as could be judged from his eyes.他并未失去知覺，這從他的眼神可以看出來。
注意：as, which引導非限制性定語從句的區別：
1）都可以代整個主句，相當于and this或and that.
2）as可放在句首，而which不能。
3）as代表前面的整個主句并在從句中作主語時，從句中的謂語必須是系動詞；如果為行為動詞，則從句中的關系代詞只能用which. 例如：
It rained hard yesterday, which prevented me from going to the park.昨天下大雨，這使得我不能去公園。
定語從句用法 10
1. 不用that的情況
(1) 在引導非限定性定語從句時。
(錯)The tree, that is four hundred years old, Is very famous here.
(2) 介詞后不能用。
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作為定語從句的關系代詞的情況
(1) 在there be 句型中，只用that，不用which。
(2) 在不定代詞，如：anything, nothing, the one, all等作先行詞時，只用that，不用which。
(3) 先行詞有the only, the very,the same,the last,just修飾時，只用that。
(4) 先行詞為序數詞、數詞、形容詞最高級時，只用that,不能用which。.
(5) 先行詞既有人，又有物時。
(6) 先行詞指物，在主句中作表語時.
(7) 為了避免重復.
(8) 先行詞是the way或the reason時，that可作關系副詞，也可省略
(9) 主句的主語是疑問詞who /which時
定語從句用法及精練
一、定語從句的概念
在復合句中，修飾某一名詞或代詞的從句叫定語從句。被修飾的名詞或代詞叫先行詞，定語從句一般放在先行詞的后面。
二、定語從句的關系詞
引導定語從句的關系詞有關系代詞和關系副詞，常見的關系代詞包括that， which， who（賓格whom，所有格whose）等，關系副詞包括where， when， why等。關系代詞和關系副詞放在先行詞及定語從句之間起連接作用，同時又作定語從句的重要成分。
三、定語從句的分類
根據定語從句與先行詞的關系，定語從句可分為限制性定語從句及非限制性定語從句。限制性定語從句緊跟先行詞，主句與從句不用逗號分開，從句不可省去，非限制性定語從句主句與從句之間有逗號分開，起補充說明作用，如省去，意思仍完整。
四、關系代詞的用法
1. that 既可以用于指人，也可以用于指物。在從句中作主語或賓語，作主語時不可省略，作賓語可省略。例如：
Mary likes music that is quiet and gentle.瑪麗喜歡輕柔的音樂。（that作主語）
The coat （that） I put on the desk is blue.我放在桌子上的那件外套是藍色的。（that作賓語）
2.which用于指物，在句中作主語或賓語，作主語不可省略，作賓語可省略。例如：
The building which stands near the train station is a supermarket.位于火車站附近的那座大樓是一家超市。（作主語）
The film （which） we saw last night was wonderful. 我們昨天晚上看的那部電影很好看。（作賓語）
3.who， whom用于指人，who 用作主語，whom用作賓語。在口語中，有時可用who代替whom， 也可省略。例如：
The girl who often helps me with my English is from England.經常在英語方面幫助我的那個女孩是英國人。（作主語）
Who is the teacher （whom） Li Ming is talking to？ 正在與李明談話的老師是誰？（作賓語）
注意：（1）當定語從句中含有介詞，介詞放在句末時，who， that， which可省略，但介詞在關系代詞前時，只能用“介詞+which/whom”結構。例如：
This is the house in which we lived last year.這是我們去年居住的房子。
Please tell me from whom you borrowed the English novel.請告訴我你從誰那借的這本英文小說。
（2）含有介詞的固定動詞詞組中，介詞不可前置，只能放在原來的位置上。例如：
This is the person whom you are looking for. 這就是你要找的那個人。
（3）that 作介詞的賓語時，介詞不能放它的前面，只能放在從句中動詞的后面。例如：
The city that she lives in is very far away.她居住的城市非常遠。
（4）關系詞只能用that的.情況：
a. 先行詞被序數詞或形容詞最高級所修飾，或本身是序數詞、基數詞、形容詞最高級時，只能用that，而不用which.例如：
He was the first person that passed the exam. 他是第一個通過考試的人。
b.被修飾的先行詞為all， any， much， many， everything， anything， none， the one等不定代詞時，只能用that，而不用which.例如：
Is there anything that you want to buy in the shop？ 你在商店里有什么東西要買嗎？
c.先行詞被the only， the very， the same， the last， little， few 等詞修飾時，只能用that，而不用which.例如：
This is the same bike that I lost.這就是我丟的那輛自行車。
d. 先行詞里同時含有人或物時，只能用that， 而不用which.例如：
I can remember well the persons and some pictures that I saw in the room.我能清楚記得我在那個房間所見到的人和一些照片。
e.以who或which引導的特殊疑問句，為避免重復，只能用that.例如：
Who is the girl that is crying？ 正在哭泣的那個女孩是誰？
f.主句是there be 結構，修飾主語的定語從句用that，而不用which.例如：
There is a book on the desk that belongs to Tom. 桌子上那本書是湯姆的。
（5）關系詞只能用which，而不用that 的情況：
a.先行詞為that， those時，用which， 而不用that.例如：
What’s that which is under the desk？ 在桌子底下的那些東西是什么？
b.關系代詞前有介詞時，一般用which，而不用that.例如：
This is the room in which he lives. 這是他居住的房間。
c.引導非限制性定語從句，用which， 而不用that.例如：
Tom came back， which made us happy. 湯姆回來了，這使我們很高興。
五、關系副詞的用法
（1）when指時間，其先行詞表示時間，在句中作時間狀語。例如：
This was the time when he arrived.這是他到達的時間。
（2）where指地點，其先行詞表示地點，在句中作地點狀語。例如：
This is place where he works.這是他工作的地點。
（3）why 指原因，其先行詞是原因，起原因狀語作用。例如：
Nobody knows the reason why he is often late for school. 沒人知道他為什么上學總遲到。
自我測試 / Test Yourself
I.單項填空。
1. -Do you know the man ______is talking with your father？
-Yes， he’s our headmaster.
A. he B. who C. which D. whom
2. Is this the river _____I can swim？
A. which B. in which C. that D. the one
3. This is the best hotel in the city _____I know.
A. where B. which C. that D. it
4. Can you lend me the dictionary ______the other day？
A. that you bought B. you bought it
C. that you bought it D. which you bought it
5. Anyone ______with what I said may put up you hands.
A. which agrees B. who agree
C. who agrees D. which agree
6. My watch is not the only thing ______ is missing.
A. that B. it C. which who
7. The man ______coat is black is waiting at the gate
A. who’s B. whose C. that of which.
8. The girl ______ is reading under the tree _____my sister.
A. which； is B. whom； was C. who； is D. who； was
9. I love places ______the people are really friendly.
A. that B. which C. where D. who
10. The world ______ is made up of matter.
A. in that we live B. on which we live
C. where we live in D. we live in
Ⅱ. 用適當的關系代詞that， which， who， whom填空。
1. The first thing ______you must do is to have a meal.
2. April 1st is the day _____is called April Fool’s Day in the west.
3. The family _____had lost everything in a big fire got much help from their friends.
4. The house _____we live in is very old.
5. Didn’t you see the man ______I talked with just now？
參考答案：
I. 1-5BBCAC 6-10 ABCCD
Ⅱ. 1. that 2. which / that 3. who / that 4. that / which 5. who/ whom/ that
定語從句用法 11
(一)、 as作連詞的用法:
as作連詞，常用來連接主句和狀語從句。
1.引導時間狀語從句，作“當...的時候”解，有“隨著...”之意，與while意義相近，強調兩個動作同時發生;或某事一發生，另一事立即發生。eg：
He shouted aloud as her ran along.他一邊往前跑，一邊高聲地呼喊。
I was startled as he opened the door.他一開門，我嚇了一跳。
as作連詞，相當于when。eg;
As a little boy (When he was a little boy)he began to learn to play piano.他小時候就開始學彈鋼琴。
2.引導原因狀語從句，作“因為，由于”解，與because的用法相近。eg;
I must stop writing now，as I have rather a lot of work to do.我必須停筆了，因為我還有許多工作要做。
3.引導方式狀語從句或比較狀語從句，作“正如，(如)像”解。例eg：
As in your country，we grow wheat in the north and rice in the south.正如(像)你們國家一樣，我們在北方種小麥，在南方種大米。(方式狀語從句)
When at Rome，do as Romans do.入鄉隨俗。(方式狀語從句)
4.引導讓步狀語從句，作“雖然，盡管”解。這時從句常用倒裝語序，即把從句中的表語、狀語或動詞原形放在as之前。eg;
Strange as it may seem，it is true.盡管這事看上去很奇怪，但卻是真的。
Try as he might，Tom could not get out of the difficulties.不管怎樣努力，湯姆還是擺脫不了困境。
1. 作“在-------期間，當----的時候”引導時間狀語從句.注意與 when、 while的用法區別。
時間狀語從句：as的用法
1.某事一發生，另一事立即發生
As the sun rose the frog dispersed 太陽一出來霧就消散。
They strolled into the garden as the music ceased. 音樂聲一停，他們就走進花園。
2.在某事發生的過程中另一事發生
I heard the murmur of their voices as I crossed the hall.
我走過大廳的時候聽到他們在嘀咕什么。(兩個動作都是一般時態)
Just as he was speaking there was a loud explosion.
正當他在說話的時候，一聲巨響。(從句用進行時態)
3. 兩個動作同時發生
He smiled as he passed. 他路過的時候笑了一下。
As she sang, the tears ran down her cheeks. 她一邊唱歌，眼淚一邊從臉頰淌下。
Helen heard the story as she washed. 海倫一邊洗衣服一邊聽故事。
He saw that she was smiling as she read. 他看到她一邊看著書一邊笑。
(兩個都是延續性動作)
We get wiser as we get older. 我們隨著年齡的增長而變得聰明起來。
(隨著時間的變化而變化)
①下列情形時,只用as, 而不用when或while。
1) 用于表示同一個人的兩種動作交替進行,指一邊----一邊. 如:
The girl sings as she goes to school.
He looked behind occasionally as he went forward in the forest.
2)表示兩個同步發生的動作或行為,意思是隨著-----的發展.如:
As time went on / by, she became more and more beautiful .
As children get older, they become more and more interested in everything.
3)表示兩個短暫行為或事情幾乎同時發生.如:
I watched her as she read the book.
I thought of it just as you opened your mouth.
Just as the flying worm hit her face, she gave a loud cry.
4)接在名詞后面表示某一個年齡段時.如:
As a young man, he was active in sports.
②when作"當……的時候"解,可以指較短的(一點)時間,也可指一段時間。如:
When I was at college, I could speak several foreign languages. When the clock struck twelve, I had slept for 2hours.
③while常表示一段較長的時間或一個過程,強調主句謂語動詞與從句謂語動詞同時發生。如:Work while you work. Play while you play.
2. As =Since 作"既然"、"由于"解,引導原因狀語從句,常用來表示已為人們所知或顯而易見的原因或理由。如:
As he’s been ill for ages, I will help him.
As / Since youre not feeling well, you may stay at home.
As he wasnt ready , we went without him.
3.As =in the way that作"像"、"按照……的方式"解,引導方式狀語從句。如:
Do as I told you.
Remember, you must do everything as I do.
4. 用于as--- as或not / so/ as ---- as中, 前一個as是副詞, 后一個as是連詞, 引導比較狀語從句。如:
They helped the old as much as possible.
I dont speak English so/ as well as she does.
5. 表示雖然, 盡管 等, 引導讓步狀語從句, 常用倒裝語序, 模式為:
adj. /adv. / n.+as +主語+謂語+主句。如:
Young as he is, he knows much.
Tired as they were, they walked on.
6. 表示也------一樣。
S he is a doctor, as was her husband.
(二)、 as作關系代詞,引導定語從句,表示正如,這一點.如:
1. 引導限制性定語從句，用在“such...as”, “the same...as”，“as...as”等結構中，常譯作“像...一樣的人(或物)”，“凡是...的人(或物)”。
eg： He wished to be such a man as Lei Feng was.他曾希望做一個像雷鋒那樣的人。
My hometown is no longer the same as it was.我的家鄉再也不像過去一樣了。
2.引導非限制性定語從句，用來指代它前面的整個句子(即先行句)，意思是“這一點”。這個分句可以位于句首、句中或句末。
eg：As is well known，oceans cover more than 70% of the earth.
我們知道，海洋占地球面積的百分之七十以上。
He is very careful, as we all know.
As is well-known, belongs to China.
另外,當先行詞被the same, such等詞修飾時,常用as來引導定語從句。如:
Such a clever girl as she can learn anything quickly.
I was reading the same book as he bought yesterday.
(三)、as作介詞的用法.
1. 作“如，像”解,表示好像。如:He dressed as a policeman.
They got united as one man.他們團結得像一個人一樣。
2. 作“充當，作為”解,表示作為, 當作。如：I found a job as a guide.
As a writer，he was famous.作為作家，他是很有名的。
3.當某人是某身份時。如：As a child , she was sent to abroad.
4.as引導的介詞短語大多用作狀語,as譯為"作為";少數情況可引起賓語補足語。如:
As a Party member, Ill take the lead in everything. (狀語)
She works as a model. (狀語)
She has me as one of her best friends.(引起賓語補足語)
(四)、作副詞的用法
as作副詞，表示程度，意為“同樣地”。在“as...as...”，“not as...as...”結構中的'第一個as是副詞，作“和/與...(不)一樣”解。
e.g. Jack is as tall as his father.杰克和他的父親一樣高。
He doesnt speak English as/so fluently as you.他的英語說得不如你流利
1 表示與------等同。
如：This dress is twice as expensive as that one.
2 像，如等。
如：As before, he remained unmoved.
五)含as的固定詞組的用法
1. as soon as作“一…就”解，引導時間狀語從句。
eg：As soon as I get to Beijing，Ill write to you.我一到北京，就給你寫信。
2.as/so long as作“只要”解，
e.g. As/So long as you study hard，youll make progress.只要你努力，你就會取得進步。
2. as if/though常用來引導方式狀語從句，作“好像，仿佛”解。如果從句中講的是非真實情況，則用虛擬語氣。
e.g. She loves the child as if/though he were her own.
她愛這個孩子如同愛自己的孩子。
3. As if/though也可用來引導表語從句，常用在“It appears/looks/seems...+as if/though”句型結構中。
e.g. It appears as if/though it is going to clear up.看起來天要晴了。
It seems as if/though he knew nothing about it.他好像對此事一無所知。4.as to作“關于，至于”解。
e.g. There is no doubt as to his honesty.他的誠實是無可置疑的。
5.as much/many as作“多達...”，“達到...之多”解。
e.g：He can earn as much as 5000 dollars a month.他每月能掙5000美元。
6.so/as far as I know作“就我所知”解，在句中作插入語。
eg： As/So far as I know，he will come here next Monday.
據我所知，他將于下星期一到這里來。
7.as a result，as a result of表示“由于...的結果”。
e.g. She died as a direct result of the accident.她的死是那次事故的直接結果。
8，as well為“也，還”之意。
e.g. Come early，and bring your brother as well.早點來，把你的弟弟也帶來。
9.so as to，so...as to若跟動詞原形，表示目的或結果。
eg：He studied hard so as to pass the exam.他努力學習以便通過考試。(表示目的)
定語從句用法 12
that的用法大全：
that的用法1：that用作指示代詞的意思是“那,那個”。可指前面提到的那件事,也可指在空間或時間上較另一事物遠的事物或人,還可指要表明的或要提及的事物、想法等。
that的用法2：that用作關系代詞時,指人或事物,同時又在從句中充當句子成分。that偶爾也可引導非限制性定語從句。
that的用法3：that還常用以代替who, whom, which,但that...which中的that用做關系代詞的先行詞。
that的用法4：that用作關系代詞時在下列情況下可以省略:①引導限制性定語從句在從句中用作賓語時; ②用在there be結構前作主語時; ③用作表語時; ④在定語從句與先行詞之間有插入語時; ⑤在先行詞way, reason, distance, place, office等作方式狀語、原因狀語或地點狀語時。
that的`用法5：that用作連詞時可引導主語從句、賓語從句、表語從句、同位語從句和狀語從句。
that的用法6：that還常引導間接引語或形容詞后面的從句。
that的用法7：that在以it作形式主語的句子中或引導賓語從句、狀語從句時常可省略。
that的用法8：that也可用于表示愿望或遺憾。
that的常用短語：
atthat
for allthat
inthat
thatis (to say)
thatsthat
that的用法例句：
1. A miracle is somethingthatseems impossible but happens anyway.
奇跡就是看似不可能，卻發生了。
2. If you wait, allthathappens isthatyou get older.
如果你等待，發生的只有變老。
3. When life gets hard and you want to give up, rememberthatlife is full of ups and downs, and without the downs, the ups would mean nothing.
當生活很艱難，你想要放棄的時候，請記住，生活充滿了起起落落，如果沒有低谷，那站在高處也失去了意義。
4. Eventually, youll learn to crythaton the inside.
終有一天，你會學會讓淚往心里流。
5. Success is not final, failure is not fatal: it is the courage to continue thatcounts.--Winston Churchill
成功不是終點，失敗也并非末日，最重要的是繼續前進的勇氣。
6. Its not about making the amazing saves. Its the little things and small thingsthat made great gatekeepers great.
偉大的門將不是靠神奇的撲救成就，而是靠注重小事和細節成功。(Tim Howard美國國家隊門將)
7. The turning point in the process of growing up is when you discover the core of strength within youthatsurvives all hurt.
當你從內心深處找到一種可以忍受一切痛苦的堅強力量時，你的成長歷程就會出現飛躍。
8. It was just thenthatI chanced to look round.
就在那時，我恰好環顧了下四周。
9. I dont want any more ofthatheavy stuff.
我再也不想碰那種麻煩事了。
10. It was the uncommittedthatLabour needed to reach.
工黨需要拉攏的是未表態者。
11. The vehiclethatpermitted both communication and acceptability was social revolution.
既能實現交流又能被廣為接受的手段就是社會革命。
12. We all knowthatfats spoil by becoming rancid.
我們都知道油脂變質后會發臭。
13. He admittedthatthe government was in "a dreadful hole".
他承認政府目前“處境極為尷尬”。
14. She probably sensedthatI wasnttelling her the whole story.
她可能意識到了我并沒有對她全盤托出。
15. He plays some passages so slowlythatthey become lugubrious.
有些段落他演奏得異常徐緩，聽上去有些憂傷。
定語從句用法 13
限定性定語從句對被修飾的先行詞有限定制約作用，使該詞的含義更具體，更明確。
限定性定語從句的用法
在引導限定性定語從句時，that有時相當于in which,at which,for which或on which
（1）Attitudes towards daydreaming are changing in much the same way that(in which) attitudes towards night dreaming have changed. 人們對白日做夢的態度正在改變，這與人們對夜間做夢的看法的變化有非常相似之處。
（2）I like the music for the very reason that(for which) he dislike it. 我出于某種原因喜歡這種音樂，而他恰恰與我相反。
（3）We arrived the day that(on which) they left. 剛好我們到的那天他們走了。
在限定性定語從句中，當關系代詞在從句中擔任動詞賓語時，關系代詞可省略。
（1）The book (that/ which) I am reading is very interesting. 我在讀的書很有趣。
（2）Is there anything (that) you wanted? 想要什么東西嗎?
限制性定語從句與非限制性定語從句用法區別：
一、 句法的功能、表現形式不同
定語從句分為限制性和非限制性兩種。限制性定語從句不可缺少先行詞，去掉它主句意思往往就不明確了，它與主句之間通常不用逗號分開；非限制性定語從句是對先行詞的附加說明，去掉它也不會影響主句的意思。如：
Do you know the professor who is speaking at the meeting? （限制性定語從句）
English is an important subject, which every student should study well. （非限制性定語從句）
二、 先行詞不盡相同
限制性定語從句的'先行詞往往是某一個詞，但非限制性定語從句的先行詞可以是一個詞，也可以是句子的一部分，甚至是整個主句，此時非限制性定語從句一般由which或as引導，as引導非限制性定語從句常用在as is said / known / expected / mentioned / reported / announced等結構中。如：
He has passed the college entrance examination, which makes his parents quite happy.
As is known to everybody, the moon travels round the earth once every month.
三、 關系詞的使用情況有所不同
1． that 不可引導非限制性定語從句。如：
Her father gave her a computer for her birthday，which pleased her a lot.
2． why 不用在非限制性定語從句中，需用for which代替。如：
I told them the reason, for which I didnt attend the party last week.
3． 關系代詞替代情況不同
關系代詞 whom 在限制性定語從句中作賓語時可用 who 代替 whom, 但 whom 在非限制性定語從句中作賓語時不可用 who代替。如：
This is the girl whom (who) I have been in love with for six years.
The young man had a new girl friend, whom he wanted to show all his love for.
4． 關系代詞省略情況不同
關系代詞在限制性定語從句中作賓語時可以省略；非限制性定語從句的所有關系代詞均不可省略。如：
She is the new student (whom / who / that) I want to introduce to you.
All the books there, which have beautiful pictures in them, were written by him.
四、 下列情形用非限制性定語從句
1. 當“不定數量詞 (如some, several) ／ 數詞 ＋ of which ／ whom”表示“整體 (which ／ whom)中的一部分”的概念時。如：
We saw many animals in the zoo, some of which are tigers．
There are fifteen new players in our team, two of whom come from Canada.
2. 當先行詞為專有名詞或被物主代詞和指示代詞修飾時，其后的定語從句通常是非限制性的。如：
My house, which I bought last year, has got a lovely garden.
Qingdao, where I have been three times, is an attractive city to foreigners.
定語從句用法 14
定語從句why的用法
關系副詞why在定語從句中也是用作狀語，表示原因;why引導定語從句時，其先行詞只有一個，那就是the reason;在許多情況下why也可以理解為for which。如：
These are the reasons why we do it. 這些就是我們這樣做的理由。
句中的why we do it為修飾the reason的定語從句，關系副詞why在此相當于for which。
Do you know the reason why she doesn’t like me? 你知道她不喜歡我的原因嗎?
句中的why she doesn’t like me為修飾the reason的定語從句，關系副詞why在此相當于for which。
why是一個比較特殊的關系副詞，它引導定語從句時，除可換成for which外，有時也可換成that，甚至省略。如：
他失去工作的主要原因是他喝酒。
正：The main reason why he lost his job was that he drank.
正：The main reason for which he lost his job was that he drank.
正：The main reason that he lost his job was that he drank.
正：The main reason he lost his job was that he drank.
定語從句when和where的用法
1. when的用法
關系副詞when在定語從句中用作狀語，表示時間，用以修飾表示時間的先行詞;在許多情況下可以理解為“介詞+which”的意思(which的意思與先行詞所表示的意思等價)，其中的“介詞”通常應根據先行詞的含與搭配來確定。如：
1988 was the year when he was born. 1988是他的出生年。
句中的when he was born為修飾the year的定語從句，關系副詞when在此相當于in which。表示在某一年，英語習慣上用介詞in，如in 1988, in 2008等，所以此處用in which。
I’ll never forget the day when I first met you. 我永遠不會忘記第一次見你的那天。
句中的when I first met you為修飾the day的定語從句，關系副詞when在此相當于on which。表示在某一天，英語習慣上用介詞on，如on that day, on Friday等，所以此處用on which。
Don’t forget the time when the wedding will start. 不要忘記婚禮開始的時間。
句中的when the wedding will start為修飾the time的定語從句，關系副詞when在此相當于at which。表示在某一時刻，英語習慣上用介詞at，如at that time, at the moment等，所以此處用at which。
2. where的用法
關系副詞where在定語從句中也是用作狀語，表示地點，用以修飾表示地點的先行詞;在許多情況下也可以理解為“介詞+which”的意思(which的'意思與先行詞所表示的意思等價)，其中的“介詞”通常應根據先行詞的含與搭配來確定。如：
What is the name of the town where you live? 你住的那個城市叫什么名字?
句中的where you live為修飾the town的定語從句，關系副詞where在此相當于in which。表示在住在某城市，英語習慣上說明live in a city，所以此處用at which。
This cross marks the spot where she died. 這個十字符號標明她死去的地點。
句中的where she died為修飾the spot的定語從句，關系副詞where在此相當于at which。表示在在某一地點，英語習慣上說明at a spot，所以此處用at which。
定語從句主要關系代詞的用法
1. that的用法
that是所有關系代詞中最常用的，它既可指人也可指物，既可用作主語也可用作賓語。如：
This is the photo (that) I took. 這就是我拍的照片。
引導定語從句的關系代詞that在此指事，且在定語從句中用作賓語，故可以省略。
They live in a house that was built 200 years ago. 他們住在一座兩百年前蓋的房子里。
引導定語從句的關系代詞that在此指物，且在定語從句中用作主語，故不可以省略。
The man that I saw told me to come here. 我見到的人讓我到這里來。
引導定語從句的關系代詞that在此指人，且在定語從句中用作賓語，故可以省略。
2. who / whom的用法
關系代詞who和whom均只能指人，不能指物;從理論上說，who是主格，在定語從句中用作主語;whom是賓格，在定語從句中用作賓語。但在實際運用中，除非是直接用作介詞后作賓語，否則凡是用賓格whom的地方。如：
I met someone who said he knew you. 我碰到一個人，他說認識你。
引導定語從句的關系代詞who在此指人，且在定語從句中用作主語，故不可以省略。
She is the girl (who, whom) you saw in school. 她就是你在學校見到的那個女孩。
關系代詞在定語從句中用作賓語，從理論上說應用whom，但也可以用who;由于是用作主語，所以它們也可以省略。
注意，如果關系代詞是直接用作介詞后作賓語，不可以用who來代替whom。如：
The girl to whom I spoke is my cousin. 我和她談話的那個姑娘是我表妹。
句中的whom直接用在介詞to的后面作賓語，故不可省略。
3. whose的用法
不要以為關系代詞whose只用于指人，其實它也可以用于指事物;whose在定語從句中主要用作定語。如：
He is the man whose car was stolen. 他就是汽車被竊的人。
It was an island whose name I have forgotten. 這是一座島，名字我忘了。
第一句中的關系代詞whose指人，第二句中的關系代詞whose 指物。
限制性和非限制性定語從句
根據從句與主句的關系是否緊密來區分，定語從句可分為限制性定語從句和非限制性定語從句兩大類。
所謂限制性定語從句，它的作用是對先行詞起修飾、限制或確定的作用，若去掉，先行詞的意思就不明確，它是不可缺少的一部分，它與先行詞的關系密不可分，不可用逗號將其分開。
而非限制性定語從句的作用則只是對先行詞起補充說明作用，它是可有可無的，與先行詞關系松散，通常用逗號將其分開。因此，有無逗號通常是區分限制性定語從句和非限制性定語從句的重要標志。
從所使用的關系詞來看，在限制性定語從句中，that可以代替who, whom和which等，但在非限制性定語從句中不能用that。如：
He changed his mind, which made me very angry. 他改變了主意，這使我很生氣。
句中的which引導非限制性定語從句，不可換成that。
Then he met Mary, who invited him to a party. 后來他遇到瑪麗，瑪麗邀請他去參加晚會。
句中的who引導非限制性定語從句，不可換成that。
另外，關系副詞when和where既可引導限制性定語從句，也可引導非限制性定語從句;但關系副詞why則只能引導限制性定語從句，不能引導非限制性定語從句。
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。
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。
以上兩句中的關系副詞when和where均引導非限制性定語從句。
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