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,詞組或代詞即先行詞。定語從句通常出現在先行詞之後，由關係詞（關係代詞或關係副詞）引出。
關係代詞有：who, whom, whose, that, which等。
關係副詞有：when, where, why等。
☆ 關係代詞和關係副詞的選用取決於先行詞及它們在定語從句中的語法成份
關係代詞 先行詞 在定語從句中充當的語法成份
Who 人 主語
Whom 人 賓語
Whose 人或物 定語
Which 物 主語或賓語
That 人或物 主語或賓語
關係副詞 先行詞 在定語從句中充當的語法成份
When 表時間的名詞 時間狀語
Where 表地點的名詞 地點狀語
Why 表原因的名詞 原因狀語
That用於表示時間、地點、方式、理由的名詞後取代when, where, why和"介詞+ which"可作關係副詞
1 關係代詞引導的定語從句
關係代詞所代替的先行詞是人或物的名詞或代詞，並在句中充當主語、賓語、定語等成分。關係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, whom, that
這些詞代替的先行詞是人的名詞或代詞，在從句中所起作用如下：
Is he the man who/that wants to see you?
他就是你想見的人嗎？（who/that在從句中作主語）
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）
2) Whose 用來指人或物，(只用作定語, 若指物，它還可以同of which互換）, 例如：
They rushed over to help the man whose car had broken down. 那人車壞了，大家都跑過去幫忙。
Please pass me the book whose (of which) cover is green. 請遞給我那本綠皮的書。
3）which, that
它們所代替的先行詞是事物的名詞或代詞，在從句中可作主語、賓語等，例如：
A prosperity which / that had never been seen before appears in the countryside. 農村出現了前所未有的繁榮。（which / that在句中作賓語）
The package (which / that) you are carrying is about to come unwrapped. 你拿的包快散了。(which / that在句中作賓語)
☆ 當關系代詞在定語從句中充當賓語時，可把關係代詞省掉
2 關係副詞引導的定語從句
關係副詞可代替的先行詞是時間、地點或理由的名詞，在從句中作狀語。
1）when, where, why
關係副詞when, where, why的含義相當於"介詞+ which"結構，因此常常和"介詞+ which"結構交替使用，例如：
There are occasions when (on which) one must yield. 任何人都有不得不屈服的時候。
Beijing is the place where (in which) I was born. 北京是我的出生地。
Is this the reason why (for which) he refused our offer? 這就是他拒絕我們幫助他的理由嗎？
2）that代替關係副詞
that可以用於表示時間、地點、方式、理由的名詞後取代when, where, why和"介詞+ which"引導的定語從句，在口語中that常被省略，例如：
His father died the year (that / when / in which) he was born. 他父親在他出生那年逝世了。
He is unlikely to find the place (that / where / in which) he lived forty years ago. 他不大可能找到他四十年前居住過的地方。
3 判斷關係代詞與關係副詞
方法一： 用關係代詞，還是關係副詞完全取決於從句中的謂語動詞。及物動詞後面無賓語，就必須要求用關係代詞；而不及物動詞則要求用關係副詞。例如：
This is the mountain village where I stayed last year.
I'll never forget the days when I worked together with you.
判斷改錯
This is the mountain village where I visited last year.
I will never forget the days when I spent in the countryside.
This is the mountain village (which) I visited last year.
I'll never forget the days (which) I spent in the countryside.
方法二： 準確判斷先行詞在定語從句中的成分(主、謂、賓、定、狀)，也能正確選擇出關系代詞/關係副詞。
例1. Is this museum ___ you visited a few days age?
A. where B. that C. on which D. the one
例2. Is this the museum ____ the exhibition was held.
A. where B. that C. on which D. the one
4 限制性和非限制性定語從句
1) 定語從句有限制性和非限制性兩種。限制性定語從句是先行詞不可缺少的部分，去掉它主句意思往往不明確；非限制性定語從句是先行詞的附加說明，去掉了也不會影響主句的意思，它與主句之間通常用逗號分開，例如：
This is the house which we bought last month. 這是我們上個月買的那幢房子。（限制性）
The house, which we bought last month, is very nice.這幢房子很漂亮，是我們上個月買的。（非限制性）
2) 當先行詞是專有名詞或物主代詞和指示代詞所修飾時，其後的定語從句通常是非限制性的，例如：
Charles Smith, who was my former teacher, retired last year. 查理史密斯去年退休了，他曾經是我的老師。
My house, which I bought last year, has got a lovely garden. 我去年買的的那幢房子帶着個漂亮的花園。
This novel, which I have read three times, is very touching. 這本小說很動人，我已經讀了三遍。
3) 非限制性定語從句還能將整個主句作爲先行詞, 對其進行修飾, 這時as和which代替的是整個主句，相當於and this或and that。As一般放在句首，which在句中。並且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, (=and that)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 (=and that) is called evaporation. 液態水變爲蒸汽，這就叫做蒸發。
☆ As還在以下幾種結構中作關係代詞引導定語從句
① the same as : He is just the same as he use to be.他還是和過去一樣
② such…as : Such passengers as survived the explosing were drowned.象那些在爆炸中倖免遇難的乘客都被淹死了
③ as…as : As many as we found were taken to the hospital.我們找到多少就送到醫院
☆關係代詞that和關係副詞why不能引導非限制性定語從句。
5 介詞+關係詞 (介詞前置：關係代詞如果在定語從句中充當介詞的賓語，可把介詞前置到關係代詞的前面，形成介詞+關係代詞的結構)
1）介詞後面的關係代詞不能省略。
2）that前不能有介詞。
3）如果關係代詞是動詞短語的賓語，動詞短語的介詞不能前置
錯誤用法：This is the girl of whom he will take care.
正確用法：This is the gril whom he will take care of
4）某些在從句中充當時間，地點或原因狀語的"介詞+關係詞"結構可以同關係副詞when 和where 互換。
This is the house in which I lived two years ago.
This is the house where I lived two years ago.
Do you remember the day on which you joined our club?
Do you remember the day when you joined our club?
☆另外還應注意的是:
①way後常用that代替in which，也可省略that
I really don't like the way (that) he talks.
That was the way in which the old lady looked after us.
②of which起形容詞的作用，相當於whose（用來指物）
They live in a house whose door (the door of which) opens to the south.
③相同的先行詞在表示不同的含義時，要根據其含義用不同的介詞。
I can't remember the age at which he won the prize.我記不起他獲得獎金的年紀
That is the age in which people live in peace and happiness. 那正是人們生活在和平幸福的時期
age在前句中意爲"年歲"，與at搭配，在後句中意爲"時期"，與in搭配。
④先行詞或定語從句中的動詞、形容詞要根據不同的具體語境選擇適當的介詞。 This is the bus on which the accident happened. 這是發交通意外的那輛巴士
This is the bus by which I came to this town. 這是我搭程去鎮上的巴士
6 Which和that 的選用
1）當先行詞是不定代詞(everything , something , anything , littlt , much)時，只能用that
Is there anything that I can help you? 有什麼我可以幫你的嗎？
2)當先行詞被序數詞所修飾時，只能用that
This is the second book that was written by the writter. 這是那個作者寫的第二本書
3)當先行詞被形容詞的最高級修飾時，只能用that
This is the best film that I have ever seen. 這是我所看過的最好的電影
4)當先行詞前有限定詞(or , every , a few , noly , some , very等)修飾時，只能用that
This is the only film that I wanted to see. 那正是我唯一想看的電影
5）在there be句型中，只用that，不用which
6）先行詞既有人，又有物時，只能用that
5)當介詞前置時，只能用which(P5-2)
6)在非限制定語從句，只能用which(並在前用 ，號與主句隔開)
7 But引導的定語從句相當於一個否定從句
There is no one but knows about the matter. 沒有人不知道這事
8定語從句和同位語從句的區別
1）同位語從句與前面的名詞是同位關係，即說明它前面名詞的內容；而定語從句與前面的名詞是修飾與被修飾關係，即限定它前面的名詞範圍，或補充一些情況。
The news that l hove passed the exam is true．我通過了考試這一消息是真的。（同位語從句，即從句所表達的意思就是前面名詞的內容。）
The news that he told me just now is true．他剛纔告訴我的消息是真的。 （定語從句，從句對前面名詞起修飾限制作用，即“他告訴我的”那個消息，而不是別的消息。）
2) 引導同位語從句的that是連詞，在從句中不充當任何成份，而引導定語從句的that是關係代詞，除起連接作用外，還在從句中充當主語、賓語或表語等。如：
The idea that computers can recognize human voices surprises many people. 計算機能夠識別人的聲音的想法使許多人感到驚奇。（that在從句中不充當任何成份。）
The idea that he gave surprises many people． 他提出的觀點令許多人感到吃驚。 （that在從句中作gave的賓語。）
定語從句練習
1易混易錯定語從句練習
有些定語從句方面的題，如果不仔細審題、不弄清句意和句子結構，就很可能把一些似是而非的東西搞混，從而降低解題的準確性。要想解決這個問題就得從準確理解句意和理清句子結構入手。
1．①Who lives in the house ＿＿＿ windows face south？
② Who lives in the house ＿＿＿ the windows face south？
A．whose B．which C．of which D．that
解析：答案是①A②C。在句①中windows前沒有定冠詞，它所缺的是定語形容詞，而whose的用法就是在定語從句中作定語且既可指人也可指物。在句②中windows前有定冠詞，所以要填的內容不能作前置定語，又因爲“房子的窗戶”用英語表達是“the windows of the house”，故可用of which引導定語從句。
2．①Is this factory ＿＿＿ you visited last year？
②Is this the factory ＿＿＿＿＿＿you visited last year？ A．that B．of which C．the one D．wher
解析：答案是①C②A。在句①中factory前沒有定冠詞，這說明this是作它的定語。這樣，句中就缺少表語，也就是說定語從句缺少先行詞，故選C（the one後省略了that）。在句②中this作主語，the factory作表語，其後帶一個that引導的定語從句，故選A
3．①John is the only one of the students who＿＿＿French．
②John is one of the students who ＿＿＿ French．
A．know B．knows C．knowing D．known
解析：答案是①B②A。在句①中的句意是“約翰是學生中唯一懂法語的那個學生”，其重心是the only one故從句謂語動詞應與one一致。在句②中的句意是“約翰是懂法語的學生中的一個”，也就是“懂法語的學生不止一個，約翰只是其中之一”，其重心是the students，故從句中謂語動詞應與students一致。
4．①When I have trouble，he is the only one ＿＿＿I can ask for help．
②When I have trouble，he is the only one ＿＿＿I can go for help．
A．whom B．to whom C．which D．to who
解析：答案是①A②B。句①中，在結構上所要添的內容在從句中作ask的賓語其句式是ask sb．for sth．，故用whom引導定語從句。在句②中，go是不及物動詞其句式是go to sb．for sth．，故用to whom引導定語從句。
5．①This is the knife ＿＿＿I usually cut my pencil．
②This is the knife ＿＿＿I usually use to cut my pencil．
A．with which B．which C．by which D．with that
解析：答案是①A②B。在句①中，定語從句的句式是cut my pencil with the knife，故用with which引導定語從句。在句②中，定語從句的結構是use the knife to cut my pencil，故用which引導定語從句。
6．①Last summer he went to Beijing，＿＿＿ he had visited twice．
②Last summer he went to Beijing，＿＿＿ he visited a lot of places of interest．
A．which B．where C．that D．there
解析：答案是①A或B②B。在句①中，所要填的內容在定語從句中應作visited的賓語，故應填關係代詞which或that。在句②中，所要填的內容在定語從句中作地點狀語，故應填關係副詞where。 7．①He still remember the days ＿＿＿we spent together．
②He still remember the days ＿＿＿we spent the summer holidays together．
A．which B．when C．where D．that
解析：答案是①A②B。在句①中，所要填的內容在定語從句中應作spent的賓語，故應填關係代詞which。在句②中，所要填的內容在定語從句中作時間狀語，故應填關係副詞when。
8．①The reason ＿＿＿ he gave us was that his car broke down on the way．
②The reason ＿＿＿ he was late was thathis car broke down on the way．
A．why B．which C．how D．what
解析：答案是①B②A。在句①中，所要填的內容在定語從句中應作gave的賓語，故應填關係代詞which。在句②中，所要填的內容在定語從句中作原因狀語，故應填關係副詞why。
2高考真題練習
1. (’03北京24)York, ________ last year ,is a nice old city.
A. that I visited B. which I visited C. where I visited D. in which I visited
【解析】 考查非限制性定語從句。是用關係代詞或者是用關係副詞引導定語從句，要根據他們在定語從句中的成份來確定，visit是及物動詞，後面需要用關係代詞作賓語，排除C，D。that 不用於非限制性定語從句中，排除A。答案爲B。
2.(’03上海41)I can think of many cases _________ students obviously knew a lot of English words and expressions but couldn't write a good essay.
A. why B. which C. as D. where
【解析】 考查定語從句。此句的先行詞是many cases，單看從句與先行詞的關係應是：students obviously knew a lot of English words and expressions but couldn't write a good essay in many cases.因此應用in which或where引導定語從句，備選答案中沒有in which，於是選where。答案爲D。
3. (’03上海44)There is a new problem involved in the popularity of private cars _________ road conditions need_________.A. that be improved B. be improved C. where oving D oving
【解析】 考查同位語從句。因爲先行詞在從句中不作任何成份，因此用關係詞that，故B、C、D均不正確。對於第2個空，need既可作實義動詞，又可作情態動詞。作實義動詞時後跟動詞不定式，即need to do sth，另外 road conditions與improve之間是被動關係，因此是need to be improved(need to be done=need doing)。譯文：私家車受歡迎所涉及到的新問題是道路狀況需要改善。答案爲A。
4.(’03北京春季31)We are living in an age ________ many things are done on computer.
A. which B. that C. whose D. when
【解析】 這是定語從句，先行詞是age,表時間，所以用when引導。答案爲D。
5.(’03安徽春季24)People have heard what the President has said; they are waiting to see _________he will do.
A. how B. what C. when D. that 【解析】 考查賓語從句。what引導賓語從句，在從句中作do的賓語。排除A、C、D。答案爲B。
6.(’03上海春季32)_________ has been announced ,we shall have our final exams next month.
A. That B. As C. It D. What
【解析】 as引導定語從句表示“正如……”，並非某個名詞或代詞是先行詞，而是整個主句所表達的內容是定語從句所修飾的。譯文：正如所宣佈的那樣，下月我們將進行期末考試。答案爲B。
7.(’02北京22)We will be shown around the city :schools ,museums ,and some other places, ________ other visitors seldom go. A. what B. which C. where D. when
【解析】 這是一個定語從句，先行詞是places，表示地點，非限定性定語從句中缺少狀語，因此用where來引導定語從句，故要填where。譯文：我們被帶領着參觀了這座城市：學校、博物館和其他一些遊人很少去的地方。答案爲C。 8.(’02上海31)Alec asked the policeman _______ he worked to contact him whenever there was an accident.
A. with him B. who C. with whom D. whom
【解析】 這是一個定語從句，the policeman是先行詞。work是不及物動詞，“work with sb”意爲“與某人共事”，所以定語從句應爲with whom he worked。譯文：無論何時發生事故時，Alec要求與他一起工作的警察與他聯繫。答案爲C。
9.(’02上海35)There's a feeling in me _______we'll never know what a UFO is-not ever.
A. that B. which C. of which D. what
【解析】 同位語從句that we'll never know what a UFO is-not ever作a feeling的同位語，解釋a feeling的具體內容。that連接同位語從句時，只起連接作用不作從句的任何成分。譯文：我有一個這樣的感覺，我們不會知道什麼是UFO--永遠不會。答案爲A。
10.(’02京、蒙、皖春季35)The famous basketball star, ______tried to make a comeback, attracted a lot of attention.
A. where B. when C. which D. who
【解析】 先行詞是The famous basketball表示人，非限定性定語從句中缺少主語，因此要填who。who在定語從句中作主語。答案爲D。
11.(’02上海春季35)Is this the reason _______at the meeting for his carelessness in his work?
A. he explained B. what he explained C. how he explained D. why he explained
【解析】 the reason後接定語從句。因爲先行詞the reason作explained的賓語，用that或which引導定語從句在從句中作賓語時省略。譯文：這就是他在會議上對他爲什麼在工作上粗心大意的理由所作的解釋嗎?答案爲A。
12.(’01全國22)The film brought the hours back to me_________I was taken good care of in that far-away village.
A. until B. that C. when D. where
【解析】 when引導定語從句(the hours的定語)，修飾先行詞the hours,when在從句中作狀語。譯文：這部電影使我回憶起我在那偏遠的村莊得到無微不至的照顧的時光。答案爲C。
13.(’01上海35)Information has been put forward ________ more middle school graduates will be admitted into universities. A. while B. that C. when D. as
【解析】 這是一個同位語從句。that引導從句作information的同位語，解釋information的具體內容。注意：that和what引導名詞性從句(主語、賓語、表語和同位語從句)的區別：that引導名詞性從句，只起引導作用，在從句中不作成分。that引導賓語從句時，that可省略，而在其他三個從句中，that雖不作成份，一般也不省略；what在這四個名詞從句中一定作成分，作主語、賓語、表語或補語。譯文：有消息說，更多的中學畢業生將進入大學。答案爲B。
14.(’01上海37)He's got himself into a dangerous situation ________ he is likely to lose control over the plane.
A. where B. which C. while D. why
【解析】 這是一個定語從句。先行詞是a dangerous situation。因爲situation的意思是“位置”，所以要填where。譯文：他已陷入飛機似乎失去控制的危險境地。答案爲A。
15.(’01京、蒙、皖春季11)John said he’d been working in the office for an hour, ______was true.
A. he B. this C. which D. who
【解析】 考查非限定性定語從句。which引導非限定性定語從句，修飾整個主句所表達的內容。答案爲C。
16.(’01上海春季30)Have you seen the film “Titanic”, ________leading actor is world famous?
A. its B. it's C. whose D. which
【解析】 這是一個定語從句，因爲先行詞the film “Titanic”和leading actors是所屬關係，所以要填寫whose。答案選C。
17.(’00全國17題)Dorothy was always speaking highly of her role in the play, _________,of course , made the others unhappy. A．who B．which C．this D．what
【解析】 這是一個非限制性定語從句，which指代Dorothy誇大自己在劇中角色的作用這件事。答案選B。
18.(’00上海28)Recently I bought an ancient Chinese vase, ________ was very reasonable. A. which price B. the price of which C. its price D. the price of whose
【解析】 這是一個非限定性定語從句。根據句意可知是花瓶的價格。在定語從句中表示“誰的”，可以這樣表達，如：I live in the room whose windows face south(名詞前沒有冠詞，用whose)=I live in the room the windows of which face south(如果名詞前有冠詞就用of which)，答案爲B。
19.(’00上海30)She found her calculator ________ she lost it.
A. where B. when C. in which D. that
【解析】 這是一個地點狀語從句，意思是“東西是在丟的地方找到的。”in which用於定語從句中，其前必須有先行詞。這個句子中沒有先行詞，所以不能填in which。答案爲A。
20.(’00上海35)Greenland, ________island in the world, covers over two million square kilometres.
A. it is the largest B. that is the largest C. is the largest largest
【解析】 有些考生把這個句子理解成了定語從句，誤選了選項B。如果這是非限制性定語從句，必須用關係代詞which引導，而不用that，即which is the largest islad in the world。實際上，the largest island in the world作Greenland的同位語。答案選D。
21.(’00京、皖春季10)The result of the experiment was very good, ________we hadn't expected.
A. when B. that C. which D. what 【解析】 這是一個非限制性定語從句，which在定語從句中作hadn't expected的賓語。這句話的意思是“實驗的結果很好，是沒有預想到的”。答案選C。
22.(’00京、皖春季16)It was an exciting moment for these football fans this year,________for the first time in years their team won the World Cup.
A. that B. while C. which D. when 【解析】 根據句子的結構可以排除that和which。再根據所提供的情境It was an exciting moment可以看出是一個時間狀語從句。注意：while的意思是during the time that表示一段時間內；when的意思是of that time that表示某個時刻，與an exciting moment相對應。這句話的意思是“當他們的隊首次進入世界盃時，對於這些足球迷來說是今年的一個令人激動的時刻”。答案爲D。
23.(’99年全國19)Carol said the work would be done by October, ________personally I doubt very much.
A. it B. that C. when D. which 【解析】 在這個非限制性定語從句中，關係代詞which代替Carol所說的話。這句話的意思是“Carol說工作將在十月完成，我個人對此表示懷疑。”答案選D。
