非限定性定語從句：非限定性定語從句的作用是對所修飾的成分作進一步說明，通常和主句間用逗號隔開，將從句拿掉後其他部分仍可成立
1. which引導的非限定性定語從句來說明前面整個句子的情況或主句的某一部分 ，that不能用於引導非限制性定語從句
例如:
Her house,which was built a hundred years ago,stood still in theearthquake.(那座房子在地震中依然聳立，它是一百多年前建造的。)
3. 有時as也可用作關係代詞
4. 在非限定性定語從句中，用who, whom代表人，用which代表事物.
5.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著個漂亮的花園。
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。
6.非限制性定語從句還能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。
非限制性定語從句只是對主句內容，或先行詞的補充、解釋或附加說明。主句與先行詞或從句之間一般用逗號分開，常常單獨翻譯。沒有它，主句意思仍然完整。引導非限制性定語從句的關係代詞有as，which，who， whom，whose等，作定語從句的主語、賓語、表語及定語。關係副詞有when，where等，作定語從句的狀語。關係代詞和關係副詞在定語從句中一般不能省。
一、as引導非限制性定語從句時，可以代主句的全部或部分內容。常表說話人關於說話的依據、態度、評論、看法等。有“正如、像”等意思。定語從句可以置主句句首、句中或句末。as後常接expect，know，report，say，see等動詞的主、被動語態句。
1． ____is known to everybody，the moon travels round the earth once every month．
A．It B．As C．That D．What
2．Mike，as we expected，attended the meeting．像我們所期望的那樣，邁克參加了會議。
3．He wasn't unconsicious，as could be judged from his eyes．他並未失去知覺，這從他的眼神可以判斷出來。
二、which引導非限制性定語從句的情況很多。
I．指代主句的全部或部分內容時，常表事實、狀態、起因等，有“這就使得、這一點”等意思，常置主句末。主句與定語從句用逗號分開。
1．Dorathy was always speaking highly of her role in the play，，of course，madethe others unhappy．
A．who B．which C．this D．what
II．指代先行詞有多種情況。定語從句置先行詞後面。
1．在“n．／pron．／num．．．．＋prep．＋ which”，“prep．＋which”定語從句裡。 1）They talked about a movie，the name of whichI'venever forgotten．他們談論過一部電影，我決不會忘記片名。
2）In Sydney theChineseteam got 28 gold medals，16．5 of which were won by women．在悉尼奧運會，中國隊奪得了28枚金牌，其中16．5枚是女子奪得的。
3）Chinahas thousands of islands，the largest of which is Taiwan．中國有數千個島嶼，其中最大的是臺灣島。
4）Chaplin went to the states in 1910，by which time he had learnt to dance and act in comedies．卓別林1910年去了美國，那時他已學會跳舞和演喜劇了。
2．表唯一性，或者就是指代先行詞的事物時。
The dam，which is the biggest in the world，is 3，830 metres long．大壩長3，830米，是世界上最大的壩。
3．先行詞是獨一無二的事物時。
The moon，which doesn't give out light itself，is only a satellite of the earth．月球本身不發光，它只是地球的一個衛星。
4．先行詞表示類屬的事物時。
Football，which is a very interesting game，is played all over the world．足球是一項非常有趣的運動，全世界都踢足球。
5．先行詞是專有名詞時。
1）Three of the biggest man-made projects in the world are theGreatWall of China，the Pyramids of Egypt and the Aswan High Dam， which is also in Egypt．世界上最大的三項人造工程是中國的長城，埃及的金字塔和阿斯旺高壩，它也在埃及。
2）TheNile，which used to flood every year，now runs more regularly below the dam．尼羅河年年漲洪水，現在比較正常地在大壩下面流過了。
6．先行詞是表人的職業、品質、身份等名詞，作定語從句的表語時。主句和定語從句之間含有對比的意思。
Mike's brother is a policeman，which he isn't．邁克的.哥哥是警察，他可不是。
7．先行詞是形容詞作定語從句的表語時。主句和定語從句含有對比的意思。
LiLingis very clever，which Li Long isn't．李玲很聰明，李瓏可不是。
8．先行詞是集體名詞表整體意思時。
My family，which has 35 people，is a large one．我家有35口人，是一個大家庭。
9．先行詞是國家名詞表地域概念時。
Lastyear he went to Egypt，which is in Africa．他去年去了埃及，埃及在非洲。
三、as，which是指代主句內容的非限制性定語從句時，表依據、評論與表事實、狀態等沒有多大差別，又在主句末時，有時可以通用。
1．He is quite pleased，as ／which can be seen from his face．他非常高興，從他的表情可以看出來。
2．You always work hard，as ／which everyone knows．大家都知道，你一向勤奮學習。
但是，上面兩句把定語從句置主句句首時，就只能用as。
3．This elephant is like a snake，as anybody can see．像任何人都能看見那樣，這頭象像條蛇。
4．Bamboois hollow，which makes it very light．竹子是空的，這就使得它很輕。 在否定意義的非限制性定語從句裡，一般用which引導。
5．He came to my birthday party，which I didn't expect at all．我完全沒有想到，他來參加我的生日聚會了。
四、who，whom，whose等引導非限制性定語從句時，指代人的普通名詞、專有名詞等。表示正是或專指先行詞等情況。在定語從句中作主語、賓語、定語等。
1．Bob's father，who worked on the project，spent four years in Egypt．鮑勃的父親從事這項工程，在埃及度過了四年。
2．Dad，this is Zheng Jie，who I knew inParis．爸，這是鄭傑，我在巴黎認識的。 這一句是用主格who代替賓格whom。
3．Hismother，whom he loved dearly， died in 1818．他非常愛戴他的母親，她死於 1818年。
4．Mr King，whose legs were badly hurt， was quickly taken to hospital．金先生的腿受了重傷，他很快就被送去住院了。
n．／pron．／num．．．．prep．whom；prep． whom；in whose ＋n．；the ＋n．of whom等引導非限制性的定語從句。
5．He spoke of a pen-pal，the name of whom ／whose name I've never forgotten．他提到過一個筆友，他的名字我從未忘記。
6．About 2，000people，many of whom were Europeans，worked on the project．大約兩千人從事過這項工程，其中很多是歐洲人。
7．In his office there are nine clerks，the youngest of whom is Mr Liu．他辦公室有9個職員，其中最年輕的是劉先生。
8．I decided to write about Chaplin，one of whose films I had seen several years before．我決定寫有關卓別林的文章，他的一部電影我幾年前就看過了。
9．We went to hear this famous singer， about whom we had heard many stories．我們去聽這個著名的歌唱家演唱。我們已經聽說了有關他的很多故事。 品黃黑MYK
10．Mr Pattis，in whose office Ms King was working，was very surprised when he found out her secret．金女士在帕蒂思辦公室工作。他發現她的祕密時感到非常驚奇。
五、when，where引導非限制性定語從句時，作定語從句的狀語。when ＝and then， where ＝and there。why不引導非限制性定語從句。
1．He was quickly taken to hospital，where a doctor wanted to examine Mr King's legs．金先生很快被送去住院，在那裡一個醫生要檢查他的腿。
2．We will put off the outing until next week，when we won't be so busy．我們把郊遊推遲到下個星期，那時我們不會那麼忙了。
3．He went to America in 1912，where and when he was noticed by an important film director．他在1912年去了美國，當時他在那裡引起了一個重要電影導演的注意。
在prep．where ／when非限制性定語從句裡，where ＝there，when ＝then。
4．His head soon appeared out of the second storey windows，from where he could see nothing but trees．他的頭很快從第二層樓的一個窗戶伸出來了，從那裡他只能看見樹木。
5．That was in 1929，since when things have been better．那是在1929年，從那時起情況就已經好轉了。
6．I wentto bed at ten，before when I was reading for an hour．我10點去睡覺，在那時以前我看了1小時的書。
有時候where ／when可以用prep．which替換。
7．The southern states wanted to set up a country of their own，where they would be free to keep black slaves．南方各州要建立一個屬於他們自己的國家，在那裡他們將自由地保留黑人奴隸。
8．I still remembered January 10，on which ／when he came to see me．我仍然記得1月10日，那一天他來看我了。
練習題：用所給的詞語填空。少數可以用多次。
A．as B．which C．who D．whom E．whose F．when G．where H．by which time I．from which J．from whom K．north of which L．some of whom M ．the biggest of which
1．Dick is going to join in the football game，____was agreed at the meeting．
2．My brother had been an engineer，____ was what he wanted to be．
3．He reached Beijing in 1998，____， some time later，he became aprofessor．
4． ____is said above，the number of the students in our school has increased．
5．Writea letter to a friend，____has some difficulties with his studies．
6．There are four rooms in the house，____ is a drawing room．
7．We will move into the new house next week，____it will be completed．
8．When lost in work，he often was，____he would forget all about eating and sleeping．
9．He is a model worker，____we can learn a lot．
10．They had to delay the sports meet till next week，____the weather will be fine．
11．The workers，____stayed there for two years，came from Africa．
12．The building over there is a hospital，____ is a small river．
13．We shall have to make a decision about Ms King，____story I've just told you．
14．Mr Liu，____I spoke of just now， would go to Australia．
15．The Nile，____electricity is produced，now runs regularly below the dam．
Keys：1．A／B2．B3．G4．A（As）5．C6．M 7．H 8．A 9．J10．F 11．L 12．K 13．E 14．C ／D 15．I
在英語中，為了避免重複，句子中的某些部分經常省略，卻給理解增加了困難。在近幾年的大學聯考試題中，省略現象也十分常見，其基本要點總結如下：
一、並列句中某些相同成分的省略。
This beeper works well, but that one doesn't (work well).
這個尋呼機工作正常, 但那個就不行。
I study at college and my sister (studies) at high school.
我讀大學，我妹妹讀高中。
二、在when, while, if,as if, though, until, once, whether, unless等連線的狀語從句中, 常省略跟主句相同的主語和be動詞。
When (I am) in trouble I always turn to her for help.
當我有困難時總是找她幫助。
The letter is to be left here until (it is) called for. 這封信留在這裡待領。
三、有形式主語it的主語從句可省略that。
It is an honor (that) I was invited to your birthday party.
我很榮幸被邀請參加你的生日聚會。
It is the third time (that)I have come to China.這是我第三次來中國。
四、在限制性定語從句中可省略作賓語的關係代詞whom, which, that。
That is the naughty boy (whom/that) we talked about last week.
他就是我們上週議論的那個淘氣男孩。
Is this the radio (that/which) you bought last Saturday?
這是你上週六買的收音機嗎?
五、在direction(方向), way(方式), distance(距離), time(時間), times(倍數)等後面所接的定語從句中常省略that, which, in which。
The direction (in which) we move a body can be changed.
我們移動物體的方向是可以改變的。
The distance (which或that)light travels in one second is 300, 000 kilometers.
光每秒走的距離是30萬公里。
六、命令句、驚歎句、部分第一人稱的陳述句、部分問句和答句中省略最為常見。
Openthe door! 開門!
Why not? 為什麼不?
Why so? 為什麼這樣?
Anybody wishing to go? 誰願意去啊?
七、用so, not或其它手段來省略上文或問句中的一部分或整個句子。
— CanEmilydo this work?埃米莉能做這項工作嗎?
—I think so.我想她行。
— Did you know anything about it?這件事你以前知道嗎?
— Not until you told me.你告訴了我, 我才知道。
八、在特定的上下文裡, 為了避免重複, 作謂語、賓語或賓語補足語的不定式再次出現時, to後的內容常承前省略, 只保留不定式符號 “to”。
I don't go swimming now but I used to.
我現在不去游泳但我過去常去(游泳)。
You can't work alone in the lab unless you are allowed to.
除非得到允許, 你不能單獨在實驗室工作。
注意：不定式to之後的動詞是be或助動詞have時, 要保留to後的be 或have。如：
China is no longer what it used to be. 中國已今非昔比。
— Have you told Allen about the concert? 你告訴艾倫音樂會的情況了嗎?
— Sorry, but I ought to have. 對不起, 我本應該(告訴她的)。
九、新聞標題要求簡練醒目, 需根據上下文的語境推敲其省略部分。
Boy 14, rescued from cliff face. (A boy of 14 has been rescued from cliff face.)
從峭壁上救下14歲的男孩。
American President to fly to London. (American President is to fly to London.)
美國總統將飛往倫敦。
十、注意在一些固定短語中某些介詞的省略。
They are (of) the same age. 他們年齡相同。
There is no use (in) explaining it to her any more.
再向她解釋這件事是無用的。
單元交際功能
表示焦慮和擔心
Howterrible!
太可怕了！
It makes me feel worried.
這讓我感到很著急。
It makes my hair stand on end.
這令我毛骨悚然。
It makes me feel uneasy when I see her.
看到她使我感到不自在。
It's a frightening thing to kill so many miners in the accident.
那麼多礦工在事故中遇難身亡，真是太可怕了。
I'm really frightened to death to see the snake.
看到蛇我嚇得半死。
He got into a total panic when he saw the drowning child.
看到孩子溺水他慌作一團。
I dare not go out alone at night.
晚上我不敢一個人外出。
What's really scary is thatthe hurricanehas caused so many losses.
真正令人恐懼的是颶風造成這麼大的損失
限制性定語從句和非限制性定語從句有四大區別，現作簡要介紹。
一、在句中作用不同
限制性定語從句對被修飾的先行詞有限定製約作用，使該詞的含義更具體，更明確。限制性定語從句不能被省略，否則句意就不完整。
非限制性定語從句與先行詞關係不十分密切，只是對其作一些附加說明，不起限定製約作用。如果將非限制性定語從句省去，主句的意義仍然完整。
二、外在表現形式不同
限制性定語從句因與先行詞關係密切，所以不可以用逗號將其與主句隔開；而非限制性定語從句與先行詞關係不十分密切，所以可用逗號將其與主句隔開。
例 1. Do you remember the girl who taught us English？
你還記得教我們英語的那個女孩嗎？
例 kis a kind of instrument which can tell people time.
鍾是一種能夠告訴人們時間的儀器。
例 3. This is the place where he used to live.
這就是他過去居住的地方。
例 g， who came to see me yesterday， is an old friend of mine.
張先生昨天來看我，他是我的一位朋友。
例 5. We walked down the village street， where they were having market day.
我們沿著村裡的大街向前走去，村民們正在那裡趕集。
析：在前三個例句中，定語從句與先行詞關係密切，為限制性定語從句，不可用逗號將其與主句隔開。在後兩個例句中，定語從句與先行詞關係不密切，為非限制性定語從句，可用逗號將其與主句隔開。
三、先行詞內容有所不同
大多數限制性和非限制性定語從句的先行詞往往為某一個詞或短語，而特殊情況下非限制性定語從句的先行詞也可為整個主句，此時非限制性定語從句常由 which 引導。
例 1. A middle-aged woman killed her husband， which frightened me very much.
一箇中年女子殺害了自己的丈夫，這令我十分恐懼。
析：由語境可知，令“我”恐懼的內容應為“中年女子殺害了自己的丈夫”這整個一件事，因此先行詞為整個主句，此時應由 which 引導定語從句。
例 2. A five-year-old boy can speak two foreign languages， which surprises all the people present.
一個五歲男孩會講兩門外語，這令所有在場的人感到非常驚訝。
析：由語境可知，令所有在場的人感到驚訝的內容是“一個五歲男孩會講兩門外語”這整個一件事，因此先行詞為整個主句，此時應由 which 引導非限制性定語從句。
四、關係詞的使用情況有所不同
（一） that 不可用於引導非限制性定語從句
所有關係代詞和關係副詞均可引導限制性定語從句，大多數關係代詞和關係副詞可引導非限制性定語從句，但 that 不可。
例 1. 他送給他母親一臺彩電作為生日禮物，這使她非常高興。
誤： He gave his mother a color TV set for her birthday， that pleased her a lot.
正： He gave his mother a color TV set for her birthday， which pleased her a lot.
例 2. 他沒通過這次考試，令我很失望。
誤： He didn't pass the exam， that disappointed me.
正： He didn't pass the exam， which disappointed me.
值得注意的是，不少同學誤認為只有 which 才能引導非限制性定語從句，這個觀點是不正確的。使用非限制性定語從句時，如果先行詞指人，則用 who ， which 或 whose 引導非限制性定語從句；先行詞指物可用 which 引導非限制性定語從句；先行詞表時間或地點且在從句中作時間狀語或地點狀語時，可用 when ， where 引導非限制性定語從句。
例 1. We'll graduate inJuly， whenwe willbe free.
我們將於七月份畢業，到那時我們就自由了。
例 2. Last Sunday they reached Nanjing， where a conference was to be held.
他們上週日到達南京，有個會議要在那裡舉行。
（二）關係代詞替代情況不同
關係代詞 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 來代替。
例 1. This is the girl whom I met in the street.
這是我在街上遇到的那個女孩。
析：先行詞 the girl 在限制性定語從句中作賓語，可用 who 代替 whom .
例 2. A young man had a new girl friend， whom he wanted to impress.
一個年輕的小夥子新交了一個女朋友，他想給她留下深刻的印象。
析：先行詞 a new girl friend 在非限制性定語從句中作賓語，不可用 who 代替 whom .
在限制性定語從句中，先行詞指人時可用 that 代替 who/ whom ，但在非限制性定語從句中先行詞指人時，不可用 that 代替 who/whom .
例：她有一個姐姐，她是教師。
誤：Shehas a sister， that is a teacher.
正： She has a sister， who is teacher.
（三）關係代詞省略情況不同
關係代詞在限制性定語從句中作賓語時可以省去，非限制性定語從句的所有關係詞均不可省。
例 1. This is the book （which/that） he lost yesterday.
這就是他昨天丟的那本書。
析：先行詞 the book 在限制性定語從句中作賓語，關係代詞 which 或 that 可以省略。
例 2. The book， which he lost yesterday， has been found.
他昨天丟了這本書，但現在已找到了。
析：先行詞 the book 在非限制性定語從句中作賓語，關係代詞 which 不可省。
［實戰演練］
1. She heard a terrible noise， _________ brought her heart into her mouth.
A. it B. which C. this D. that
2. Have you ever been to Xi'an， _________ I left ten years ago.
A. which B. whose C. that D. /
3. The weather turned out to be very good， _________ was more than we could expect.
A. what B. which C. that D. it
4. His English， ________ used to be very poor is now excellent.
A. which B. that C. it D . whom
of the roads were flooded， __________ makes o
ur journey more difficult.
A. that B. it C. which D. who
6. I'll find a nice girl， _________ I want to marry.
A. who B. whom C. that D. which
7. I'll come at ten， ________ I'll be free.
A. which B. that C. when D. what
8. She has two brothers， _________ are teachers.
A. who B. that C. whom D. /
9. Which answer is NOT true？
This is the factory ________ I visited yesterday.
A. that B. which C. / D. where
10. I still remember the days _________ I spent in Beijing.
A. when B. what C. that D. during
Key：
1. B 2. A 3. B 4. A 5. C
6. B 7. C 8. A 9. D 10. C
