從句講解
定語從句
一。I 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, whom, that
這些詞代替的先行詞是人的名詞或代詞，在從句中作主語和賓語。例如：
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）
II. 關系副詞引導的定語從句
關系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）關系副詞when, where, why的含義相當于"介詞+ which"結構，因此常常和"介詞+ which"結構交替使用。
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代替關系副詞，可以用于表示時間、地點、方式、理由的名詞后取代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。
III.判斷關系代詞與關系副詞
方法一： 用關系代詞，還是關系副詞完全取決于從句中的謂語動詞。及物動詞后面無賓語，就必須要求用關系代詞；而不及物動詞則要求用關系副詞。例如：
This is the mountain village where I stayed last year. 這是我去年呆過的山村。
I'll never forget the days when I worked together with you.我永遠不會忘記與你共事的日子。
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.
習慣上總把表地點或時間的名詞與關系副詞 where, when聯系在一起。此兩題錯在關系詞的誤用上。
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/關系副詞。
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
答案：例1 D，例2 A
例1變為肯定句： This museum is ___ you visited a few days ago.
例2變為肯定句： This is the museum ___ the exhibition was held.
在句1中，所缺部分為賓語，而where, that, on which都不能起到賓語的作用，只有the one既做了主句的表語，又可做從句的賓語，可以省略關系代詞，所以應選D。
而句2中, 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詞組，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、定、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） 。
IV. 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，其后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。
3） 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。
V. 介詞+關系詞
1）介詞后面的關系詞不能省略。
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。
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?
二。定語從句應注意問題
I。that, which區別
關系代詞that的幾種情況。
1． 先行詞為all， everything， nothing， something， anything， little， few， much等不定代詞時。先行詞被all， each， few， much， every， no， some， any等不定代詞修飾時。如： There is little that I can use． 幾乎沒有什么我能用的了。
All the books that you need are here． 你所需要的書都在這兒。
2．先行詞被序數詞或形容詞最高級修飾時。如：
This is the first composition that he has written in English．這是他用英語寫的第一篇作文。
4．先行詞既有人又有物時。如：
He talked about the teachers and schools that he had visited． 他談到了他曾拜訪過的老師和學校。
5．主句是以who或which開頭的疑問句時。如：
Who is the man that is speaking over there？ 在那里說話的人是誰？
6．先行詞被the only，the very， the last等修飾時。如：
This is the very gun that I am looking for． 這正是我在找的槍。
7． 關系代詞在從句中作表語時。如：
He is not the young man that he was thirty years ago．他已不是三十年前的那個年輕人了。
關系代詞which
（1）在引導非限定性定語從句時(不能放句首)
He can speak English fluently，which impressed me most.他的英語講得很流利，給我留下了深刻印象。
（2） 介詞后
This is the house in which I have lived for 2 years.這就是我居住了兩年的房子。
（3）在非限制性定語從句中，即可指一個詞，也可指整個句子。
She married again, which was unexpected.
I lost my watch, which is not found yet.
II。which, as 區別
as 和which在引導非限制性定語從句時，這兩個關系代詞都指主句所表達的整個意思，且在定語從句中都可以作主語和賓語。但不同之處主要有兩點：
(1） as 引導的定語從句可置于句首，而which不可。
As we know, smoking is harmful to one's health.
（2）the same… as；such…as 中的as 是一種固定結構, 和……一樣……。
I have got into the same trouble as he (has).
III。介詞+關系代詞
介詞+whom（人）主，謂結構
介詞+which（物）主，謂結構
（介詞）+whose+名詞+主，謂結構=and+介詞+形容詞形物主代詞+名詞+主謂結構
（介詞）+which+名詞+主，謂結構=and+介詞+this或that +名詞+主謂結構
He is the person to whom you can turn for help.
The pencil with which he was writing broke.
He is the man from whose house (=and from his house) the picture were stolen.
We traveled together to Paris, at which place(=and at this place) we parted company.
IV.分隔式定語從句
有些定語從句和現行詞之間插入一個詞組，短語或別的成分，叫做分隔式定語從句
He arrived Hangzhou in 1984, where he became manager 2 years later.
名詞性從句
主語從句：應注意問題
1. 主語從句的語序
主語從句要求使用陳述句語序，而非一般疑問句語序。如：
What surprised me most was that the little girl could play the violin so well.
How he was successful is still a puzzle.
2. 連接詞的選用
（1）that和what的選用
that和what都可引導主語從句。what除起連接作用外，還在名詞性從句中充當某些成分，可作從句的主語、賓語或表語。而that在名詞性從句中不充當任何成分，無詞義，只起連接詞作用。
What he wants is a book. That light travels in straight lines is known to all.
（2）if和whether的選用
引導主語從句，不能用if，只能用whether。如：
Whether we will hold a party in the open air tomorrow depends on the weather.
（3）其它連接代詞和副詞的選用
根據主語從句的具體意義，正確的選擇who, which, when, where, why, how等連接詞，這些連接詞既有疑問含義，又起連接作用，同時在從句中充當各種成分。如：
When we shall hold our sports meet is not decided. Who broke the glass yesterday is not clear.
（4）whatever / whoever的功用
whatever, whoever在主語從句中不含疑問意義。它引導主語從句，并在從句中作主語、賓語、表語等。whatever = anything that; whoever = anyone who。要注意和whatever, whoever引導的讓步狀語從句的區別
Whoever breaks the law should be punished. （主語從句）（＝Anyone who breaks the law should be punished. ）
Whoever breaks the law, he should be punished. （讓步狀語從句）（＝No matter who breaks the law, he should be punished. ）
3. it構成的主語從句
（1）由連詞that引導的主語從句，在大多數情況下會放到句子的后面，而用代詞it作形式主語。
It is well-known that the earth moves around the sun.
需要注意的是，it作形式主語代替主語從句時，要注意和as引導的定語從句的區別。試比較：
It was reported that the US was under the terrorist attack. （主語從句，有that，無逗號）
As was reported, the US was under the terrorist attack.
（定語從句，無that，有逗號）
（2）常見用it作形式主語的復合句結構
It is a fact （a good idea / a pity / a shame / no wonder / good news…）that…如：
It”s a pity that you missed the film.
It is necessary （clear / true / strange/ important / possible…）that…
需要注意的是，這類主語從句中，謂語動詞很多為“（should）＋動詞原形”，即要用虛擬語氣。
It is necessary that you （should）master the computer.
It is important that a student learn English well.
It is said that he was killed in the earthquake. 據說他在地震中喪生了。
It seems （happened / appears / doesn”t matter / makes no difference / …）that …
It seems that they will win the game.
It makes no difference whether he will attend the meeting or not.
4。主語從句連接詞that不能省略 That he didn’t like her was obvious.
The problem is when we can get a pay rise.
B 連接表語從句的連接詞有：that, what, who, when, where, which, why,
He has become a teacher.=He has become what he wanted to be ten years ago.
She has remained there for an hour.=She has remained where I stood yesterday for an hour.
His suggestion is good.=His suggestion is that we should stay calm.
The question is confusing.=The question is when he can arrive at the hotel.
who will travel with me to Beijing tomorrow.
how I can persuade her to join us in the party.
whether the enemy is marching towards us.
False: The question is when can he arrive at the hotel.
Right: The question is when he can arrive at the hotel.
B 不可以用if，而用whether 連接表語從句(as if 例外）。
False: The question is if the enemy is marching towards us.
Right: The question is whether the enemy is marching towards us.
Right: It looked as if he had understood this question.
C 不像賓語從句，在有表語從句的復合句中，主句時態和從句時態可以不一致。
Right: The question is who will travel with me to Beijing tomorrow.
Right: The question is why he cried yesterday.
that引導賓語從句時，特別是在口語中 that常可省略。但在下列情況下，引導賓語從句的that一般不省略。
1）當由兩個或兩個以上的that引導的從句作同一個動詞或介詞的賓語時，第二個以及以后從句中的that不宜省略。如：
He said（that）he couldn't tell you right away and that you wouldn't understand．
2）當動詞think， make，feel，consider等后用it作形式賓語來代替that引導的賓語從句時。
We think it necessary that we should practise spoken English every day．
He said that even if it rained，he would be able to come．
二者引導賓語從句時，一般可換用。但在下列情況下，通常只能用whether而不能用if。
We didn't know whether or not she was ready．比較We didn't know whether／if she was ready or not．）
Please let me know whether you like it．（若該句用if，也可理解為：如果你喜歡它，請告訴我。）
When I was a boy，my teacher told me that the earth is round．
He told me he goes to the park every day．
1）在表示建議（suggest），要求（demand，insist）和命令（order）等動詞后的賓語從句中，常用“（should）＋動詞原形”的形式來表示虛擬語氣。如：
I suggest that we（should）have a rest now．
I wish I could fly．（用過去式表示與現在事實相反的愿望）
I wish I had known it before．（用過去完成式表示過去未實現的愿望）
I wish you would stay a little longer．（用would或would ＋動詞原形來表示將來的愿望）
這是一個常見的否定轉移句型。使用時常把賓語從句中的否定詞not移至主句中，即主句謂語用否定式而從句謂語則用肯定式。該結構常譯為“我（我們）認為……不……”。如：
這是一個復雜特殊疑問句。它由一個一般疑問句（do you think）和一個特殊疑問句（疑問詞＋其它句子成分）合并而成。如：
When do you think he will be back？你認為他會什么時候回來呢？
注：常用于上面兩結構的主句動詞除think外，還有believe，suppose，imagine等。
The news that our team had won the match spread the whole country.
有時如果主句的謂語動詞較短，為保持句子平衡，避免頭重腳輕，同位語從句也常與要說明的分詞分開。
Word came that he died yesterday.
1. 表示陳述意義時通常用that。注意that不能省略。例如：
The fact that he didn”t pass the college entrance examination disappointed his parents.
The king made a promise that he would make anyone rich if one could cure his illness.
2. 當名詞doubt用在否定句中時，其后的同位語從句應用that引導；而用在肯定句或疑問句中時則可以用其他詞來引導。
I never have the doubt that you can look after yourself.
Some people have the doubt how such a little boy can lift so heavy a box.
3. 表示“是否”的意思時只能用whether，不能用if。這一點與主語從句相似。例如：
The question whether he can finish the work within two days remains unknown.
This student asked a good question why pollution can”t be stopped.
兩者作用不同，主語從句和賓語從句都是從句在主句當中充當主語和賓語；而同位語從句是一個跟在某一名詞后并具體說明該名詞內容的從句。例如：
（1）That the pop singer will come to this city excited everybody.
（2）Everybody is excited to hear that the pop singer will come to this city.
（3）The news that the pop singer will come to this city excited everybody.
同位語從句的名詞只能是前面提到的幾個有限的、有一定內涵的名詞；而定語從句的先行詞可以是名詞、代詞、主句的一部分或是整個主句。
定語從句是從句對其先行詞的修飾或限制，屬于形容詞性從句的范疇；而同位語從句是從句對其前名詞的解釋，該名詞與同位語從句的關系可以用“主系表”來表達。例如：
We have all heard the news that our team has won.
The news is that our team has won.
有些引導詞如：how, whether可以引導同位語從句，但不能引導定語從句。what不可以引導定語從句，但卻可以引導同位語從句。例如：
I have no idea what has happened to him.
<1>The order that we should throw away our luggage was received yesterday.
<2>The order （that）we received yesterday was that we should throw away our luggage.
狀語從句是副詞性從句，它在句子中擔任狀語，修飾主句的動詞、形容詞或副詞。根據修飾的方面，狀語從句可以分為以下九種。
whenever When I came into the room, he was writing a letter.
We shall go there whenever we are free.
狀 when I was walking along the street when suddenly someone patted me on the shoulder from behind.
我正在街上走著，這時忽然有人從后面拍我的肩膀。 when意為“這時”或“在那個時候”,可以看作是并列句,這種用法的when分句一般位于句末。
while While it was raining, they went out.
他不在的時候我在。 while指“在某一段時間里”，“在…期間”，while引導的動作必須是持續性的。
as He hurried home, looking behind as he went.
他趕快回家，不時地一邊走一邊向后看。 as引導持續性動作，強調主句和從句的動作同時發生。
句 before Be a pupil before you become a teacher.
after He arrived after the game started.
till We waited till (until)he came back .
我們一直等到他回來。 如主句動詞是持續性動作，常用肯定式，表示“直到…為止”
時 until She didn’t stop working until eleven o’clock .
Until he had passed out of sight, she stood there.
她站在那里看著，直到看不見他的身影。 如主句動詞是瞬間動詞，常用否定式，表示“直…才”“在…以前不”,從句放在句首表示強調，一般用until
Great changes have taken place in China since 1978.
I had hardly got home when it began to rain.
我剛一到家，就下雨了。=Hardly had I got home when it began to rain.
No sooner had we got to the station than the train left.
Hardly had we begun when we were told to stop.
every time, by the time, the moment
等 Every time I travelled by boat, I got seasick.
The moment I heard the song, I felt cheerful.
Next time you come ,you’ll see him.
下次你來的時候，就會見到他。 在時間狀語從句中，不能用將來時或過去將來時，而要用現在時或過去時代替將來時。
wherever Where there is a will, there is a way.
Where there is water there is life.
You are free to go wherever you like.
Wherever you go, you must obey the law.
無論你去哪都要遵守法律。 where與wherever意義基本相同，但后者語氣較強，多用于書面語。
狀 because I came back late yesterday because I was on duty.
昨天我回來晚了，因為我值班。 because用來回答why 的問題，語氣最強一般放在主句之后
句 since Since everyone is here, let’s begin our meeting.
既然大家都到了，我們開始開會。 since表示既然或全已知的理由,稍加分析即可表明的原因,多放句首
因 as As he didn’t know much English, he looked up the word in the dictionary .
由于他英語懂得不多，他在字典中查閱這個單詞。 從句常放在句首，說明原因，主句說明結果，常用于口語中。
句 now that, seeing that Now (that) the weather has cleared up, we can start our journey.
Seeing (that) he was badly ill, we sent for the doctor.
鑒于他病情嚴重，我們派人去請醫生去了。 seeing (that), now that 和since, as 意義相似，他們都有“鑒于某個事實”的意思，that可以省去。
lest = for fear that I shall write down your telephone number that I may not forget.
We’ll tell you the truth so that you can judge for yourself.
They worked harder than usual in order that they could finish the work ahead of time .
Put on more clothes lest (= for fear that ) you should catch cold.
多穿點衣服，以免患感冒。 目的狀語從句中常用情態動詞may (might) can (could) ,should 等放在動詞之前，從句往往放在主句之后，主從句之間不用任何標點符號
so…that We turned up the radio, so that everyone heard the news.
He was so excited that he couldn’t say a word.
他十分激動，以致一句話都說不出來。 so that前有逗號為結果狀語從句。
句 such…that He gave such important reasons that he was excused.他說出了這么重要的理由，得到大家的諒解。
It is such an interesting novel that all of us want to read it.
It is so interesting a novel that all of us want to read it.
這是一本十分有意思的書，大家都想看。 such…that的such后面跟名詞，如果名詞是單數就要用such a /an…that還可以轉換用so…that，語氣較強
so far as Difficulties are nothing if we are not afraid of them.
We shall go there tomorrow unless it rains.
= We shall go there tomorrow if it doesn’t rain.
So/As long as you work hard, you will succeed.
In case I forget, please remind me about it .
So far as I know, the book will be published next month.
unless從句的謂語只能用肯定式。unless和if…not同義，unless是書面語，if…not是口語，通常二者可以換用。
條件狀語從句中的謂語動詞的時態一般要用現在時或過去時代替一般將來時或過去將來時。
as though Draw a cat as I taught you .
He acted as if (though) nothing had happened.
They treat the black boy as if (though) he were an animal.
他們對待這黑孩子仿佛他是一頭牲口。 此處as譯為，按照或正如
as if或as though的意義和用法基本一樣。從句中可以用現在時表示可能符合事實，也可以用虛擬語氣。
although Although (Though) he was over sixty, (yet) he began to learn French.
We were not tired though (although) we had worked all day.
even though I’ll go even if (though) it rains tomorrow.
即使明天下雨，我也要去。 even if 和even though的意思為“即使”“縱使”有退一步設想的意味，多用于書面語中。
as Child as he is , he knows a lot .
Cold as it is, (= Though it is cold,)the children play outdoors.
雖然天氣冷，但孩子們仍在戶外玩。 as引出的狀語從句多用于書面語，它比用
though或although引導的從句，語氣強，更有表現力，從句常放在句首，語序部分倒裝。
no matter (who, what when, where which, how…) Do it no matter what others say.
No matter how busy he was, he studied English every day.
No matter who takes up the matter for me ,I shall be very grateful.
不管誰為我處理這件事，我都將非常感激。 no matter……與 who-ever引導的讓步狀語從句意義基本一 樣，no matter……引導的從句可是以位于主句前或主句后。
Whoever comes, he will be welcome.
such…as Mary is as old as my sister.
He doesn’t run so (as) fast as Jack (does).
Henry is not such a good worker as Peter .
享利這個工人不如彼得那樣好。 連詞表示同程度級的比較，肯定句用as…as否定句可用not as…as 或not so…as
句 than She has made greater progress this year than she did last year.
He bought fewer books than I (did).
他買的書比我買的少。 表示不同程度之比較，主句中用比較級的形容詞或副詞。
…the more The more you read, the better you understand.
The more tickets you sell, the more money you will get.
The harder you work, the greater progress you will make.
越暖和越好。 the more…the more 意思為越…越…，通常的語序為從句在前主句在后，這兩個the都是表示程度的副詞，用在比較級的形容詞或副詞前面。
句 that We are sure (that )the four modernization will be realized in China .
I’m sorry (that) I didn’t have time to write you sooner.