资源简介

(共20张PPT)
Section Ⅲ　Using language
Unit 1 Face values
主语从句
观察下面句子，写出黑体词部分在句中所作句子的成分。
①That she should be ungrateful cut him to the heart.
②Whether she would play the part is still doubtful.
③What he needs is more experience.
④Who will teach us English next term has not been told yet.
⑤Whichever one of you breaks the window will have to pay for it.
⑥How the telephone was invented is a long story.
⑦When she'll be back depends much on the weather.
⑧It is quite possible that something has gone wrong with the machine.
[自主归纳]
1．句①是由that引导的主语从句，that在从句中 成分，只起连接作用。
2．句②是由whether引导的主语从句，whether在从句中 成分，只起连接作用。
3．句③、④、⑤是由 引导的主语从句，连接词分别在从句中作 、 和 。
4．句⑥、⑦是由 引导的主语从句，连接词在从句中一般作
。
5．句⑧用 作形式主语，把主语从句放到句尾。
不充当句子
不充当句子
连接代词
宾语
主语
定语
连接副词
状语
it
一、主语从句
在句中充当主语的从句称为主语从句。英语中带有主语从句的句型可分为两大类：一是直接将主语从句放在主语的位置上；二是用it作形式主语，将真正的主语从句后移，放在句子后部。从句作主语时，谓语动词一般用单数形式(what从句作主语时，如果含有复数概念，谓语动词可用复数形式)。
That mathematics is the base of other science is known to all of us.
＝It is known to all of us that mathematics is the base of other science.
众所周知，数学是其他科学的基础。
二、主语从句的类型
1．that、whether引导的主语从句：连接词只起连接作用，在从句中不充当句子成分，可用it作形式主语。
That he won the game made a tremendous stir in our country.
他赢得比赛一事在我国引起了巨大轰动。
Whether it will do us harm or good remains to be seen.
此事对我们是利还是弊还有待观察。
It depends on how hard he works whether one can succeed (or not).
一个人能否成功取决于他工作努力的程度。
[名师点津]
if有时也可引导主语从句，但只能用it作形式主语，if从句后置。
It is doubtful if they will come.
他们是否会来值得怀疑。
2．连接代词what(ever)、which(ever)、who(ever)、whom (ever)、whose引导的主语从句：这类连接词除了起连接作用外，还在从句中充当一定的句子成分，如可作主语、宾语、表语或定语。
What she did after that is not clear to us.
在那之后她做了什么，我们不清楚。
Whatever is worth doing at all is worth doing well.
凡是值得做的事，都值得好好地做。
Which of all those ways is the best is uncertain.
还不能肯定所有那些方法中哪一个最好。
Whom we should serve is a question of vital importance.
我们应当为谁服务是一个极为重要的问题。
Whose carelessness spoilt the work must be made clear.
必须查清是谁的粗心大意坏了事。
It is still open to question who is to head the group.
谁领导这个小组还未定下来。
3．连接副词when、where、how、why引导的主语从句：这类连接词在从句中常作状语，也可用it作形式主语代替主语从句。
When and where the meeting will take place has not been decided yet.
开会的时间和地点还未确定下来。
Why he did it will remain a puzzle forever.
他做此事的原因将永远是个谜。
lt is not clear how accurate the results are.
这些结果的精确程度还不清楚。
三、it作形式主语的主语从句
1．It is/was＋形容词＋主语从句．
It is quite clear that the crime has been done deliberately.
很明显这是故意犯罪。
It was clear enough what she meant.
她的意思已经够清楚了。
lt is uncertain why he denied the charge.
不确定他为什么否认了指控。
2．It is/was＋名词＋主语从句．
It is a good thing that we do morning exercises every day.
我们每天做早操是件有益的事。
It is a complete mystery what caused the accident.
是什么引起了这场事故完全是个谜。
It's not my business how she chooses to live.
她选择什么样的生活不关我的事。
3．It is/was＋过去分词＋主语从句．
It is required that the machine should be maintained at regular intervals.
这台机器需要定期保养。
It is not yet known whether they will send a delegation to the conference，but we hope they will.
还不了解他们是否会派代表团来参加会议，但是我们希望他们(会派代表团来)。
Has it been decided where we are to hold the meeting
我们开会的地点决定了吗？
4．It＋不及物动词＋主语从句．
It happened that I wasn't there that day.
碰巧那天我不在那里。
It doesn't matter what she looks like.
她的外表怎么样并不重要。
5．It is/was＋介词短语＋主语从句．
It is of great importance whether we can improve our scientific research or not.
我们能否提高我们的科学研究是极为重要的。
[名师点津]
在“It is important/necessary/natural/essential/impossible ...＋that从句”和“It is demanded/suggested/required/requested/proposed ...＋ that从句”中，从句的谓语动词用虚拟语气，即(should) do形式。
It is necessary/essential that a scientific worker (should) know a foreign language.
一名科学工作者务必精通一门外语。
It is desired that remote control (should) be introduced in this system.
有人想要把遥控装置引进该系统。
四、主语从句中需注意的问题
1．从句要用陈述句语序
What we will do next should be decided.
应该决定一下我们下一步该做什么。
2．主谓一致
(1)从句作主语时，主句的谓语一般用单数形式。
Where he will get a job after graduation has puzzled him much.
毕业后到哪儿找份工作使他很困惑。
[名师点津]
what引导主语从句时，有时主句的谓语动词应与主句中作表语的名词保持一致。
What the school needs most are books.
这所学校最需要的是书。
(2)如果由and连接两个或两个以上的主语从句作主语时，谓语动词一般用复数形式；由两个或多个连接词引导一个主语从句时，谓语动词一般用单数形式。
When they will start and where they will go have not been decided yet.
他们将在什么时候动身以及要去哪里还没定下来。
When and where the movie will be shown is not clear.
这部影片何时何地上映还不清楚。
Ⅰ.单句语法填空
1． we understand things has a lot to do with what we feel.
2．Exactly the potato was introduced into Europe is uncertain，but it was probably around 1565.
3．I think impresses me about his painting is the colours he uses.
4． they should refuse to sign the petition required great courage.
5． is clear enough that she hasn't been able to convince Mike.
6． they would support us was a problem.
How
when
what
That
It
Whether
7． you are coming to Beijing is the best news I have heard this year.
8． they will come is unknown.
9． is a problem whether Mr Li will teach us how to repair the computer.
10． he has no interest in art is obvious.
Ⅱ.用主语从句完成下列句子
1．他在如此短的时间内写完这篇作文使我们十分惊讶。
in such a short time surprised us all.
2．“我们为谁而学习”是个很重要的问题。
is a question of great importance.
That
Whether
It
That
That he finished writing the composition
“Whom we study for”
3．是什么事使她生气还不清楚。
was not clear.
4. 她被挑选上这事在她村子里引起了轩然大波。
made a tremendous stir in her village.
5．我们将邀请多少人还是个问题。
is still a question.
What made her angry
That she was chosen
How many people we are to invite

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