1、I went to visit the American author who wrote a number of books about China.

2、I ate the soup my aunt prepared.

3、I have an arrangement with my bank, by which they let me use their money and repay them next month.

4、He sent her a letter, in which he said that he was sorry for what he had done to her.

1.定語從句

定語從句所修飾的先行詞可以是名詞或代詞，也可以是一個句子。定語從句通常位於先行詞之後，由關係代詞或關係副詞引導。

*限制性定語從句

限制性定語從句修飾先行詞，對先行詞起修飾作用，緊接先行詞之後，無逗號，若省去，原句意思不完整。引導定語從句的關係代詞有who,whom,whose,which,that等。who,whom,whose用於指人，whose有時也可指物，相當於of which；which用於指物；that既可指人也可指物，但只用於限制性定語從句中。關係代詞除了引導定語從句，替代先行詞外，還在從句中擔任主語、賓語、定語等。

The computers and cables which make up the Internet are owned by people and organizations.

Those who live alone or who are sick may have trouble in getting close to other people.

The girl whose parents died in an accident is living with her grandmother.

1)當先行詞是all,anything,everything,something,nothing等不定代詞或先行詞前有first,last,any,few,much,some,no,only以及形容詞最高階修飾時，只能用關係代詞that引導從句。

That is all that I"ve heard from him.

He"s the first person that I"m going to interview this afternoon.

2)關係代詞的省略

在從句中作賓語的關係代詞常可省略。關係代詞緊跟介詞，作介詞賓語時不可用that，只可用which或whom引導從句，並且不可省略，但當介詞位於賓語從句句末時，作為介詞賓語的關係代詞仍可用that，也可省略。

This is one of those things with which we have to put up.

This is one of those things (which\that) we have to put up with.

3)引導定語從句的關係副詞有when,where,why等。關係副詞在從句中作狀語，意義上相當於一個“介詞+which”的結構。

Even in comic books where(=in which) there are no words,the stories are fully expressed through the drawings.

No one knows the reason why(=for which) he was so angry that day.

*非限制性定語從句

非限制性定語從句既可修飾先行詞，也可修飾整個主句，起補充說明作用，與主句之間有逗號隔開，若省去，原句意思不受影響。不可用that引導非限制性定語從句。關係詞不可省略。

Every object has a gravitational pull,which is rather like magnetism.

*“介詞+which\whom\whose”引導的定語從句

“介詞+which\whom\whose”可引導限制性定語從句，也可引導非限制性定語從句，該結構中介詞的選擇取決於從句謂語動詞的固定搭配，或先行詞的習慣搭配。

This is the computer on which he spent all his savings

It is written by a person with whom we are all familiar.

*as引導的定語從句

as引導的定語從句主要用於“such...as”及“the same...as”的結構中，代替先行詞是人或物的名詞。as引導非限制性定語從句時，代替整個主句，從句可位於主句之前、之後或中間。

These are not such problems as can be easily solved.(as代替先行詞problems)

As is mentioned above,no single company or group can control what happens on the Internet.(as代替主語)

2.主語從句

1）主語從句可直接位於主語的位置，如果從句較長，謂語又較短，可用it作形式主語，而將從句放在句末。常見的句型有：

*It is a fact\a pity\a question\good news that...

*It seems\appears\happened\has turned out that...

*It is clear\important\likely\possible that...

*It is said\reported\estimated\has been proved that...

It is said that comic books create a connection between people of the same generation.

It seems that the performance is very useful.

2)what引導的主語從句表示“...的東西時”，一般不用it作形式主語。

What we lack is experience.

3)what,who,when,why,whether等詞含有各自的疑問意義，但它們引導的主語從句，都用陳述語序。

How the plan is to be carried out should be discussed again.

I did know why I felt like crying.

3.賓語從句

1）賓語從句可位於及物動詞、介詞和某些形容詞後。連詞that常可省略。介詞後一般接疑問詞引導的賓語從句。in that(因為),except that(除了),but that(只是）已構成固定搭配，其他介詞後一般不接that引導的賓語從句。

*I promised that I would change the situation.

*All this is different from what American young people would say about friendship.

*He is certain that watching so much television is not good for children.

*This article is well-written except that it is a bit too long.

2）關於賓語從句連詞的選擇：

*They believe that the computer will finally take the place of human beings.(他們相信計算機終將代替人類。) (從句本來就是陳述句)

* I wonder whether I should say something for him to the headmaster. (我不知道是不是該為他在校長跟前說點什麼。) (從句來源於一般問句Shall I say something for him to the headmaster?)

3)賓語從句後如有賓補，要用形式賓語it來代替，而把賓語從句移至賓補之後。

He has made it clear that he would not change his mind.

4)在think,believe,suppose,expect等動詞後的賓語從句中，如果謂語是否定的，一般將否定詞移至主句謂語上，賓語從句則變成肯定形式。

He didn"t think that the money was well spent.

4.表語從句

在句子中作連繫動詞的表語的從句,它位於主句中的系動詞之後。表語從句出現在結構為“主語+系動詞+表語從句”的句子中。表語從句除可用that,what,when,why,whether,how等引導外，還可由because,as if(though)等引導。that常可省略。如主句主語為reason,只能用that引導表語從句，不可用because.

*Perhaps the most important thing to remember is that there is no one common type of life in America.

*The reason why so many people died there is that there were not enough food supplies.

*It looks as if successful international cultural communication will make the world smaller.

5.同位語從句

同位語從句用於對前面出現的名詞作進一步說明，一般用連詞that引導，由於先行名詞的意義不同，也可用whether,who,when,where,what,why,how等引導。常見的先行詞有fact,idea,belief,news,hope,conclusion,evidence,suggestion,order,problem,report,decision.有時由於謂語較短，將同位語從句位於謂語之後。

She finally made the decision that she would join the fashion show.

I had no idea how many books I could borrow at a time.

The news came that their team had won the championship.

6.狀語從句

*時間狀語從句

引導時間狀語從句的從屬連詞和片語有：

1）when,whenever,while,as,after,before,since,till,until,once等。

We have learnt quite a lot about it since we came here.

2)as soon as,hardly(scarcely)...when,no sooner...than,each(every) time,the moment,immediately(that)等。

As soon as I sent an e-mail message,I received positive responses.

The moment he heard the good news,he jumped with joy.

*地點狀語從句

引導地點狀語從句的連詞是where,wherever.

Wherever she went,she took her little daughter with her.

*原因、結果和目的狀語從句

1）引導原因狀語從句的從屬連詞有：because,as,since,now(that),seeing that,considering that,in that等。

Considering that he is a freshman,we must say he is doing well.

2)引導結果狀語從句的連詞有：so...that,such...that

,so that,that,so等。

Mickey Mouse is so attractive that the children are reluctant to leave.

3)引導目的狀語從句的連詞有：so that,in order that,for fear that,lest等，從句常使用may,might,can,could,would等情態動詞。

We got up early this morning so that we could catch the first bus to the railway station.

*條件和讓步狀語從句

1）引導條件狀語從句的連詞和片語有if,unless,as(so) long as,on condition that,in case,provided(providing) that,supposing等。

As long as you have the right equipment,you can use a telephone line to transmit computer data.

2)引導讓步狀語從句的連詞和片語有though,although,whether,even though,even if,no matter what(when,how...),whatever(whenever,wherever,however....)等。though,even if等引導狀語從句可轉換成含有as的部分倒裝結構，具有強調意義。其結構為“形容詞（副詞、動詞、名詞）+as+主語+謂語”。

No matter what you may say,I would not change my mind.

Young as he is,he is quite experienced in this work.(=though he is young)

Child as he is,he can speak English fluently.(=though he is a child)

*方式狀語從句

引導方式狀語從句的連詞有as,just as,as if,as though等。as if,as though引導的狀語從句中，謂語動詞常用虛擬語氣，表示與事實相反。

The young man made the experiment just as the teacher had taught him.

Everything went on as usual as if nothing had happened.