新概念英语第二册语法总结：名词性从句（1）主语从句知识要点：名词性从句包括：主语从句、表语从句、宾语从句和同位语从句。引导名词性从句的连词有：A.连词：that, whether, if（这三个词都不作从句的成分，同时， that 无含义，而whether 和 if 都表“是否”）B.疑问代词：who, whom, whose, what, whichC.疑问副词：when, where, why, how （一）主语从句：在复合句中充当主语的从句。1.that 引导主语从句that 引导主语从句时不同于其他的连词，既无词义也不作成分，只起单纯的连接作用，且通常不可以省。为了强调 that 引导的主语从句而置之于句首时，that 不可省。①That the driver could not control his car was obvious.②That she was chosen made us very happy.③That he will come is certain.④That he would take the risk is true.⑤That he should have married her isn't surprising.★通常，that 引导主语从句时用 it 做形式主语，把从句置于句尾，此时 that 有时可省。例如：①It was obvious that the driver could not control his car.②It made us very happy that she was chosen.③It is certain that he will come.④It is true that he would take the risk.⑤It isn't surprising (that) he should have married her.★如果以 that 从句为主语的句子是疑问句，就只能用先行词 it 结构。例如：①Is it certain that he will come?②Is it true that he would take the risk?▲it 做形式主语有以下几种不同的结构：(1)It + be + 形容词+ that-从句①It is likely that he will come.②It is strange that she has ever trusted him.③It is important that he (should) attend the meeting.④It is best that he (should) go.此句型在表示惊讶、喜悦、遗憾等感情色彩时，that 从句中的谓语动词也常用 (should) + v 原形。It is strange that no one should have objected to the plan.(2)It + be +名词+ that-从句It is common knowledge that the whale is not a fish.It's a pity that he should have catched the train.(3) It + be + -ed 分词 + that 从句It is said that he is a famous w...
