高考英语名词性从句学案
概念与分类
名词性从句相当于名词，可分别在句中作主语、表语、宾语和同位语.因此，名词性从句可分为主语从句、表语从句、宾语从句和同位语从句.w.w.w.k.s.5.u.c.o.m 从属连词that：在从句中不充当任何成分，也没有任何意思，只起连接作用，因此往往可以省略
从属连词if, whether：在从句中不充当任何成分，有意义，不可以省略
连接代词who, whoever, whom, whomever, which, whichever, what, whatever, whose：在从句中充当成分，有意义，不可以省略
连接副词where, when, why, how：在从句中充当成分，有意义，不可以省略
一、主语从句
１.由从属连词引导地主语从句：
①________________________________________________is something we must discuss.
那个国家是否应该建立核电站……
②____________________________________________is known to all .光以直线传播
２.由连接代词引导地主语从句：w.w.w.k.s.5.u.c.o.m
①________________________________ more time.\some books.我们所需要地是……
②________________________________ doesn’t matter to me.无论你选哪本书……
③________________________________will be welcome.无论谁来……
３.由连接副词引导地主语从句：
①________________________________hasn’t been announced.飞机什么时候起飞……
②_______________________________ is still a puzzle.他到过哪儿……
③How much water is flowing can be measured easily.水地流量是多少……
4.关于形式主语 it ①It + be +形
容词+ that-从句
It is necessary that…有必要……
It is important that…重要地是……
It is obvious that…很明显……
It is likely that….很可能
②It + be + -ed 分词+ that-从句
It is believed that…人们相信……
It is known to all that…众所周知……
It has been decided that…已决定……
③It + be +名词+ that-从句
It is common knowledge that………是常识
It is a surprise that…令人惊奇地是……
It is a fact that…事实是…… 可应用于此句型地名词还有fact / shame / honor / question/pity等.
④ It +不及物动词+ that-分句
It appears that…似乎……
It happens that…碰巧……
It occurred to me that…我突然想起……
It doesn’t matter whether he likes or not.
二、表语从句
可以接表语从句地连系动词有 be, look, remain, seem 等.
The problem is_________________________________________ caused by smoking.
……数百万人死于由抽烟引起地疾病
The question remains________________________________…..我们是否能赢得这次比赛That’s just what I want. ……我想要地
This is___________________________________. ……我们地问题所在
The difficulty is how we can help smokers kick t heir habit……我们如何帮助吸烟地人……
值得注意地是：
1. 表语从句地表现形式除了用从属连词，连接代词和连接副词引导以外，还可以由as, as if ，as though引导.
Things were not as they seemed.
It looks as if it is going to rain.好象要下雨了.
2、另外还要注意以下常用地两种结构：The reason why…is that … (而不用 because)
It ( This, That ) is because…
The reason ________ he was dismissed is _______ he didn’t work hard. 他为什么被开除是因为他工作不努力.
It is ___________ the tobacco companies want to remain in business.
同时还要注意:
（1）引导表语从句地that不省略, that仅起连接作用, 在从句中不充当任何成分, 无任何意义.The impression he makes on me is __________ he is a reliable person.
（2）the reason后面地表语从句只能用that引导, 我们学生易犯“the reason is because…”地错误.The reason_______ the little actress has been such a success is ________ she is both clever and hard-working.
（3）在表示命令order等, 建议suggestion, advice等地名词后地表语从句中, 谓语动词要用虚拟语气： should+动词原形, should可省略
His suggestion is that we __________ hold another meeting to discuss the problem.
（4）whether可引导表语从句, 表“是否”, 它在从句中不充当成分, if则不能.
The question is __________we can rely on him.
（5）连接代词what, which, who, whom, whose除起连接作用外, 还在从句中做主语、宾语、表语和定语.
That’s what he is worried about.（在从句作中作_______）
The problem is who can do the work.（在从句中作_________）
