1、语法简单句并列句+复合句并列句名词性从句宾语从句表语从句主语从句同位语从句3种t hat 通常可以省略动词+宾语从句介词+宾语从句含义结构系动词+从句t hat 不做成分，但不能省略句子作表语，跟在系动词后面含义从句作主语(陈述语序)常见类型t hat/w het her引导连接代词引导（w hat，w ho,w hose,w hom,w hi ch，w hoever,w hat ever等）连接副词引导（w hen，w here，w hy，how 等）i t 作形式主语?I t i s done+主语从句 I t i s adj/n +主语从句 连接词+陈述句t hat 不能省略在抽象名词后
2、，解释说明内容 idea,opinion,evidence,question,doubt,reason,theory,belief,possibility,chance,hope,contenti on,guarant ee，f act.特殊句式I find it unbelieveable that you love me.The executives are talking about whether they should pass the proposal.Part of the problem is that many homeless adults are addicted to
3、alcohol or drugs.When he will come is unknown.That she survived the accident is a miracle.Whether he will come is unknown.Whoever breaks the law should be punished.Where he will go is unknown.It is said that.It is believed that.It is necessary that.It is a pity that.形容词性从句副词性从句主语过长，借I t 作形式主语It make
4、s him worried that his hair is turning gray.What he said is true.Which student will win is unknown.形容词+宾语从句Researchers admit(v.)that their study does not answer the question.i t 作形式宾语主语+谓语+i t+宾补+t hat从句扩展：主语+谓语+i t+宾补+t o doI find it hard to finish the homework.I find it clear that you are wrong.Th
5、e judge says she will pass the bill.Times are not what they used to be.含义一个句子做同位语（解释说明）However,the conventional view that education should be one of the very highest priorities for promoting rapid economic development in poor countries is wrong.I got an information that Xiao Zhan would come to Beijing.I have got a message that he wont come to visit you.必要的是.遗憾的是，.,这.的是，.