初高中衔接英语教材--名词性从句

初高中衔接教材------名词性从句

定义：在复合句中起词名词作用的句子叫名词性从句(Noun Clauses）。名词性从句的功能相当于名词，可分别作主句的主语、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、宾语从句和同位从句。学习内容：1. 掌握各名词性从句的连接词的用法。2. 连接词的分类 3. 连词that, if, whether 的用法及区别

4. 熟悉各名词性从句的句型，能辨别是哪一种名词性从句。

解题技巧：先通读全句，分析句子成分，判断是哪一种从句。如果句子中缺少主语、表语、宾语，就用what,who,which 等连接代词；如果不缺，则根据意思选择连词that, whether, if或者连接副词where, when, how, why等。

（一）引导名词性从句的连接词

1）连接代词：who, whose, whom, what, which，whoever, whatever有词义，在从句中必须充当句子成分，如主语、表语、宾语或定语等。

2）连接副词：when, where, why, how有词义，在从句中必须充当成分，只能作状语。

3）连接词：that, whether, if, as if

▲that 无词义，在从句中不充当成分，引导宾语从句时可省略；其它（主语从句，表语从句，同位语从句）中连词that不能省略。if ，whether，as if虽有词义，但在从句中不担任成分。if 只能用于宾语从句，其它（主语从句，表语从句，同位语从句）中只能用whether, 不能用if.

Whether he will come or not doesn’t matter much. (主语从句）

It looks as if it is going to rain. (表语从句）

He asked me which team could win the game. (宾语从句）

You have no idea how worried we are. (同位语从句）

The fact that he lied again greatly surprised us. (同位语从句）

注意：连接代词与连接副词在句中不再是疑问词，因而从句中谓语不用疑问式。连接代词与连接副词在从句充当句子成分，连接词whether 和if（是否），as if（好象）在从句中不充当句子成分，只起连接作用。根据句义，如果连接代词与连接副词，whether、if 和as if都用不上时，才用that作连接词（that本身无任何含义）。

（二）主语从句:在复合句中其语法作用是主语的句子，叫主语从句。

1）主语从句位于句首

e.g. （1）That he finished writing the composition in such a short time surprised us all.

（2）Whether we will go for an outing tomorrow remains unknown.(注意：不能把whether改为if，因为if 不能引导主语从句)

（3）Whatever you did is right.

（4）Who will be our monitor hasn't been decided yet.

（5）What caused the accident remains unknown.

（7）When we will start the work is important.

2）为了避免句子头重脚轻，用it作形式主语，主语从句放在句末。

e.g.（1）It doesn’t matter so much whether you will come or not.

（2）It is true that he has made a very important discovery in chemistry.

（3）It is a pity that we won't be able to go to the south to spend our summer vacation.

（4）Is it likely that it will rain in the evening ?

3）it 作形式主语的主语从句

有时为了考虑句子平衡，通常在主语从句处使用形式主语it，而将真正的主语从句移至句末。

(1) 对于以连词that引导的主语从句，通常用形式主语it替代主语从句：

It is no surprise that Bob should have won the game.

It is necessary that you（should）master the computer.

It is said that thirteen is an unlucky number.

It is reported that over 300 million people in China are suffering from near-sightedness.

It is known to all that the earth is round.

（三）表语从句：在复合句中作表语的完整句子，位于be动词或系动词之后，说明主语是什么或者怎么样。e.g.（1）The question was who could go there.

（2）He has become what he wanted to be ten years ago.

（3）She has remained where I stood yesterday for an hour.

（4）His suggestion is that we should stay calm.

（5）It seems as if it is going to rain.

（6）The question is whether the enemy is marching towards us. (注意：不能把whether改为if，因为if不能引导表语从句)

（7）What she couldn’t understand was why fewer and fewer students showed interest in her lessons.

（四）宾语从句：宾语从句在复合句中作宾语，引导宾语从句的连词that一般可省略。

e.g.I hope (that) everything is all right.

1）介词之后的宾语从句，不可用which或if连接，要分别用what或whether。

e.g. I’m interested in whether you’ve finished the work. I’m interested in what you’ve said.

▲2）whether与if都可以引导宾语从句，常可互换，但下面情况不能互换。

①宾语从句是否定句时，只用if，不用whether。 e.g. I wonder if it doesn’t rain.

②宾语从句中的whether 与or not直接连用，就不能换成if。

e.g. I don’t know whether the report is true or not.