1.主語(yǔ)從句
1）主語(yǔ)從句可直接位于主語(yǔ)的位置，如果從句較長(zhǎng)，謂語(yǔ)又較短，可用it作形式主語(yǔ)，而將從句放在句末。常見(jiàn)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...
如：
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(dǎo)的主語(yǔ)從句表示“...的東西時(shí)”，一般不用it作形式主語(yǔ)。
What we lack is experience.

3)what,who,when,why,whether等詞含有各自的疑問(wèn)意義，但它們引導(dǎo)的主語(yǔ)從句，都用陳述語(yǔ)序。
How the plan is to be carried out should be discussed again.
I did know why I felt like crying.

2.賓語(yǔ)從句
1）賓語(yǔ)從句可位于及物動(dòng)詞、介詞和某些形容詞后。連詞that?？墒÷?。介詞后一般接疑問(wèn)詞引導(dǎo)的賓語(yǔ)從句。in that(因?yàn)?,except that(除了),but that(只是）已構(gòu)成固定搭配，其他介詞后一般不接that引導(dǎo)的賓語(yǔ)從句。如：
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)賓語(yǔ)從句后如有賓補(bǔ)，要用形式賓語(yǔ)it來(lái)代替，而把賓語(yǔ)從句移至賓補(bǔ)之后。
He has made it clear that he would not change his mind.

3)在think,believe,suppose,expect等動(dòng)詞后的賓語(yǔ)從句中，如果謂語(yǔ)是否定的，一般將否定詞移至主句謂語(yǔ)上，賓語(yǔ)從句則變成肯定形式。
He didn't think that the money was well spent.

3.表語(yǔ)從句
表語(yǔ)從句出現(xiàn)在結(jié)構(gòu)為“主語(yǔ)+系動(dòng)詞+表語(yǔ)從句”的句子中。表語(yǔ)從句除可用that,what,when,why,whether,how等引導(dǎo)外，還可由because,as if(though)等引導(dǎo)。that?？墒÷?。如主句主語(yǔ)為reason，只能用that引導(dǎo)表語(yǔ)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.

4.同位語(yǔ)從句
同位語(yǔ)從句用于對(duì)前面出現(xiàn)的名詞作進(jìn)一步說(shuō)明，一般用連詞that引導(dǎo)，由于先行名詞的意義不同，也可用whether,who,when,where,what,why,how等引導(dǎo)。常見(jiàn)的先行名詞有fact,idea,belief,news,hope,conclusion,evidence,suggestion,order,problem,report,decision.有時(shí)由于謂語(yǔ)較短，將同位語(yǔ)從句位于謂語(yǔ)之后。如：
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.