(共17张PPT)
高考英语语法完全讲解
名词性从句
在句中起到名词所能充当的句子成分的从句称之为名词性从句,名词常用来作主语、宾语、表语、同位语,因此,对应的名词性从句可以分为四大类:主语从句、宾语从句、表语从句、同位语从句。
1、作句子主语的从句叫作主语从句。
2、为避免句子头重脚轻,常用形式主语it代替主语从句,把主语从句置于句尾。常用的句型有:It is/was+形容词/名词/过去分词+that从句。
Whether he can come to the party on time depends on the traffic.
It’s a great pity that they didn’t get married.
It is true that the man on the left is a well-known writer here.
It is required that all members be present.
1、作句子宾语的从句叫作宾语从句。宾语从句在句中可以作及物动词或者介词的宾语。
2、that引导宾语从句,一般不充当介词的宾语,但可作in和except的宾语,其它介词后要用形式宾语it。
Hearing that his son was badly wounded, he hurried to the hospital to see him.
There was a discussion about whether the proposal was practical.
Your composition is well written except that there are some spelling mistakes.
位于系动词之后作表语的从句叫表语从句。
The problem is who is to pay and when we can start.
同位语从句说明其前面名词的具体内容。通常由that引导,常接同位语从句的名词有:news, conclusion, possibility, rumor, certainty, story, word, mystery, idea, doubt, hope, truth, question, belief, fact, message, evidence, information, explanation, rule, probability, question, wish, thought, statement, report, opinion, principle等。
The news that the United States was hit by terrorist attacks took the whole world by surprise.
He must answer the question whether he agrees to it or not.
① that在句中没有意义,在从句中不充当句子成分,只起到连接的作用。
It is decided that the meeting should be put off till next Monday.
② that引导动词后的宾语从句时,可以省略,但引导其它名词性从句时,不可以省略。但如果宾语从句是并列句时,引导第二个分句的that不可以省略。
He said (that) he was late for school again and that the teacher would punish him.
whether可以引导四种名词性从句,if只能引导宾语从句和不放在句首的主语从句,即用it作形式主语。
在下列情况下只能用whether引导宾语从句:
(1)作介词宾语;
(2)whether...or (not)结构中;
(3)后接动词不定式。
The question is whether they can take our advice.
It is still a question whether they can take our advice.
Whether they can take our advice is a question.
It is doubtful whether/if they can take our advice.
连接代词不仅起到连接主从句的作用,而且在名词性从句中充当主语、宾语、定语或表语。
The question is who can take his place.
We are so upset about what we should do next.
Whoever is late for the meeting should be punished.
连接副词不仅起到连接主从句的作用,而且在名词性从句中充当状语。
It makes no difference where we shall have the meeting.
They couldn’t understand why I refused it.
The problem is where we should stay.
一、what的用法
what有时保留它原有的疑问意义,表示“什么”;有时作双重连接代词,相当于all that或the thing that;what本身已包括先行词,所以前面无需再用先行词。
I don't know what she is doing.(疑问代词)
I understood what he said.(连接代词)
All what he said was reasonable.(错)
What he said was reasonable.(正)
All that he said was reasonable.(正)
That is a car what I can't afford. (错)
That is a car that (which) I can't afford.(正)
二、who/whom与whoever/whomever的区别
who/whom意为“谁”,引导名词性从句时,带有疑问色彩。whoever/whomever意为“无论谁、任何人”,相当于anyone who/whom,没有疑问色彩。
Who will take the position is under discussion.
Whoever takes the position should be responsible for our company.
三、what/whatever与which/whichever的区别
what/whatever意为“什么/无论什么”,描述的事物在上下文中没有范围;which/whichever意为“哪个/无论哪个”,描述的事物在上下文中有范围。
To be honest, I can hardly understand what/whatever you have said.
Here is the dress. This is what I have been dreaming of.
Here are many beautiful dresses. You can choose whichever you like.
四、because和why引导表语从句
because引导表语从句时,表示原因;why引导表语从句时,表示结果。
Jim got up late. That was because the clock went wrong.
The clock went wrong. That was why Jim got up late.