1.定語(yǔ)從句
定語(yǔ)從句所修飾的先行詞可以是名詞或代詞，也可以是一個(gè)句子。定語(yǔ)從句通常位于先行詞之后，由關(guān)系代詞或關(guān)系副詞引導(dǎo)。
→限制性定語(yǔ)從句
限制性定語(yǔ)從句修飾先行詞，對(duì)先行詞起修飾作用，緊接先行詞之后，無(wú)逗號(hào)，若省去，原句意思不完整。引導(dǎo)定語(yǔ)從句的關(guān)系代詞有who,whom,whose,which,that等。who,whom,whose用于指人，whose有時(shí)也可指物，相當(dāng)于of which；which用于指物；that既可指人也可指物，但只用于限制性定語(yǔ)從句中。關(guān)系代詞除了引導(dǎo)定語(yǔ)從句，替代先行詞外，還在從句中擔(dān)任主語(yǔ)、賓語(yǔ)、定語(yǔ)等。如：
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(dāng)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以及形容詞最高級(jí)修飾時(shí)，只能用關(guān)系代詞that引導(dǎo)從句。如：

That is all that I've heard from him.
He's the first person that I'm going to interview this afternoon.

2)關(guān)系代詞的省略
在從句中作賓語(yǔ)的關(guān)系代詞?？墒÷?。關(guān)系代詞緊跟介詞，作介詞賓語(yǔ)時(shí)不可用that，只可用which或whom引導(dǎo)從句，并且不可省略，但當(dāng)介詞位于賓語(yǔ)從句句末時(shí)，作為介詞賓語(yǔ)的關(guān)系代詞仍可用that，也可省略。如：
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(dǎo)定語(yǔ)從句的關(guān)系副詞有when,where,why等。關(guān)系副詞在從句中作狀語(yǔ)，意義上相當(dāng)于一個(gè)“介詞+which”的結(jié)構(gòu)。如：
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(yǔ)從句
非限制性定語(yǔ)從句既可修飾先行詞，也可修飾整個(gè)主句，起補(bǔ)充說(shuō)明作用，與主句之間有逗號(hào)隔開(kāi)，若省去，原句意思不受影響。不可用that引導(dǎo)非限制性定語(yǔ)從句。關(guān)系詞不可省略。如：
Every object has a gravitational pull,which is rather like magnetism.

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*“介詞+which\whom\whose”引導(dǎo)的定語(yǔ)從句
“介詞+which\whom\whose”可引導(dǎo)限制性定語(yǔ)從句，也可引導(dǎo)非限制性定語(yǔ)從句，該結(jié)構(gòu)中介詞的選擇取決于從句謂語(yǔ)動(dòng)詞的固定搭配，或先行詞的習(xí)慣搭配。如：
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(dǎo)的定語(yǔ)從句
as引導(dǎo)的定語(yǔ)從句主要用于“such...as”及“the same...as”的結(jié)構(gòu)中，代替先行詞是人或物的名詞。as引導(dǎo)非限制性定語(yǔ)從句時(shí)，代替整個(gè)主句，從句可位于主句之前、之后或中間。如：
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(yǔ))

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2.狀語(yǔ)從句
→時(shí)間狀語(yǔ)從句
引導(dǎo)時(shí)間狀語(yǔ)從句的從屬連詞和詞組有：
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(diǎn)狀語(yǔ)從句
引導(dǎo)地點(diǎn)狀語(yǔ)從句的連詞是where,wherever.
Wherever she went,she took her little daughter with her.

→原因、結(jié)果和目的狀語(yǔ)從句
1）引導(dǎo)原因狀語(yǔ)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(dǎo)結(jié)果狀語(yǔ)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(dǎo)目的狀語(yǔ)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(tài)動(dòng)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(yǔ)從句
1）引導(dǎo)條件狀語(yǔ)從句的連詞和詞組有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(dǎo)讓步狀語(yǔ)從句的連詞和詞組有though,although,whether,even though,even if,no matter what(when,how...),whatever(whenever,wherever,however....)等。though,even if等引導(dǎo)狀語(yǔ)從句可轉(zhuǎn)換成含有as的部分倒裝結(jié)構(gòu)，具有強(qiáng)調(diào)意義。其結(jié)構(gòu)為“形容詞（副詞、動(dòng)詞、名詞）+as+主語(yǔ)+謂語(yǔ)”。
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(yǔ)從句
引導(dǎo)方式狀語(yǔ)從句的連詞有as,just as,as if,as though等。as if,as though引導(dǎo)的狀語(yǔ)從句中，謂語(yǔ)動(dòng)詞常用虛擬語(yǔ)氣，表示與事實(shí)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.