更多精彩资源,请点击英语教师网

 

 

从句专题

高三牛津版选修9Unit 1 语法——主语从句 

一、从句定义：句子中除了谓语，其他成分都可用一个具有完整的主谓结构，但不能独立使用的句子来承担。承担什么句子成分就叫什么从句。

二、从句的分类：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）、定语从句、状语从句。

三、引导从句的词叫引导词，如：what,which,how等。

 

第一章 主语从句

 

主语从句由下列引导词引导，引导词不能省略。

连词：that,whether

连接代词：what,whatever,who,whoever等

连接副词：when,where,how,why

1.    第一大类：由连接代词引导的主语从句：

Which team will win the championship is still not clear.

 

Who will be the monitor makes no difference.

 

Whoever comes first should open the window.

 

说明：连接代词在句子中充当句子成分，不能省略，翻译时不能把他们译为疑问句。由它们引导的主语从句可以用形式主语it引导，如果句子是疑问形式，则必须用it的结构。

eg:1. Who let out the news remained unkonwn.

=It remained unknown who let out the news.

2.      Which is right isn’t known to us.

=It isn’t known to us which is right.

2.     第二大类： 由连接副词引导的主语从句：

When they will arrive is not known yet.

 

Where we’ll spend our holiday has not been decided.

 

说明：连接副词在句子中充当句子成分，不能省略，翻译时不能把他们译为疑问句。由它们引导的主语从句可以用形式主语it引导，如果句子是疑问形式，则必须用it的结构。

eg: 1. When we’ll start is not clear.

     =It is not clear when we’ll start.

2. How this happened is still a question.

3. 第三大类： 由连词引导的主语从句：

That the driver was drunk is obvious.

 

Whether you come or not doesn’t concern me.

 

 

说明：连词that在句子中不担任成分，不能省略，本身没有词义.

4. 第四大类： 主语从句的后置：

主语从句因为太长，往往置于句子的后部，而用it作形式主语。

it 作形式主语的固定句型：

句型一： It + be + adj.(包括起形容词作用的分词) + 从句

eg: It is not likely that this situation will continue very long.

句型二： It + be + n. + 从句

eg: It is common sence that the whale is not a fish.

句型三： It + v.(+宾语或状语) + 从句

eg: It seems to me that he won’t come taday.

句型四： It + be + 过去分词 + 从句

eg: It is said that the temple was built over one thousand years ago.

注：带有主语从句的疑问句必须将主语从句后置，用it作形式主语。

eg: 1. Is it certain that he will help us tomorrow?

2. Has it been decided when we’ll have the final examination?

5． 第五大类： 主语从句中的虚拟语气：

（1）表示愿望、建议、命令等含义的动词后面的主语从句用虚拟语气。谓语动词用虚拟语气“should + 动词原形” ， should 可以省略。

这类动词主要有：demand,insist,desire,order,require,suggest,recommend,advise

eg: It is suggested that he (should) walk an hour every day in order to lose weight.

(2) 一些形容词后的主语从句用虚拟语气。谓语动词用虚拟语气“should + 动词原形” ， should 可以省略。

这类形容词主要有：necessary,important,impossible,natural,strange,essential,

appropriate,vital,imperative.

eg: It is strange that no one (should) support this plan.

(3) 有些形容词或名词，可以与带有虚拟语气的主语从句结合使用，表示惊奇，不满，喜悦，遗憾等感情色彩。

eg: It’s a pity that he (should) miss the opportunity to study in Beijing.

6. 第六大类： 主语从句和不定式结构的互换：

当主句的谓语动词是expect,feel,say,think,know,report或主句的表语是certain,

probable,likely等词时，带有主语从句的这种结构也可以转换成相应的不定式结构。

eg: 1. It was known that Jack failed the entrance examination again.

=Jack was known to have failed the entrance examination again.

2.It’s quite likely that she will come back in two weeks.

=She is quite likely to come back in two weeks.

7. 第七大类： 以关系代词what,whatever,whoever 等引导的主语从句：

what 有时可用来表示 the thing which 这种意思，引导从句，表示一样东西或一件事情。

who,whom,which,what 可以和ever 构成合成词，和 what 一样引导从句，ever 起强调作用。

此类主语从句不能用形式主语 it 引导，它们在句子中充当成分，不能省略，语序为陈述语序。

eg: 1. What he said at the meeting is important.

=The thing that he said at the meeting is important.(定语从句)

2.Whoever leaves the office should tell me.

=Any one who leaves the office should tell me.(定语从句)