主語(yǔ)從句的概念:
如果一個(gè)句子在復(fù)合句中充當(dāng)一個(gè)主語(yǔ),那么這個(gè)句子就是主語(yǔ)從句。主語(yǔ)從句通常由從屬連詞that,whether,if和連接代詞what,who,whichwhatever,whoever以及連接副詞how,when,where,why等詞引導(dǎo)。that在句中無(wú)詞義,只起連接作用。
主語(yǔ)從句用法:
1、主語(yǔ)從句的引導(dǎo)詞:
主語(yǔ)從句通常由連詞that和whether、連接代詞或連接副詞以及關(guān)系代詞型what引導(dǎo):
如:That he is still alive is a wonder. 他還活著,真是奇跡。
When we arrive doesn't matter. 什么時(shí)候到?jīng)]有關(guān)系。
What we need is money. 我們需要的是錢(qián)。
What I want to know is this. 我想知道的就是這一點(diǎn)。
Whether they would support us was a problem. 他們是否會(huì)支持我們還是一個(gè)問(wèn)題。
2、主語(yǔ)從句與形式主語(yǔ)it:
有時(shí)為了考慮句子平衡,通常在主語(yǔ)從句處使用形式主語(yǔ)it,而將真正的主語(yǔ)從句移至句末。這分三種情況:
(1)對(duì)于以連詞that引導(dǎo)的主語(yǔ)從句,通常用形式主語(yǔ)代主語(yǔ)從句:
如:It's a pity that he didn't come. 很遺憾他沒(méi)來(lái)。
(2)對(duì)于以連接代詞(副詞)引導(dǎo)的主語(yǔ)從句,可以使用形式主語(yǔ)代主語(yǔ)從句,也可直接在句首使用主語(yǔ)從句:
如:Whether they would support us was a problem. 他們是否會(huì)支持我們還是一個(gè)問(wèn)題。
It was a problem whether they would support us. 他們是否會(huì)支持我們還是一個(gè)問(wèn)題。
(3)對(duì)關(guān)系代詞型what引導(dǎo)的主語(yǔ)從句,通常不用形式主語(yǔ),總是主語(yǔ)從句放在句首:
如:What we need is money. 我們需要的是錢(qián)。
What I want to know is this. 我想知道的就是這一點(diǎn)。
(4)如果句子是疑問(wèn)句,則必須用帶形式主語(yǔ)it的結(jié)構(gòu):
如:Is it true that he is the girl's father? 他是那女孩的父親,是真的嗎?
How is it that you are late again? 你怎么又遲到了?
3、連詞that的省略問(wèn)題:
引導(dǎo)主語(yǔ)從句的連詞that有時(shí)可省,有時(shí)不能省,其原則是:
若that引導(dǎo)的主語(yǔ)從句直接位于句首,則that不能省略;
若that引導(dǎo)的主語(yǔ)從句位于句末,而在句首使用了形式主語(yǔ)it,則that則可以省略:
如:That you didn't go to the talk was a pity. 很遺憾你沒(méi)去聽(tīng)報(bào)告。(that不可省)
It was a pity(that) you didn't go to the talk. 很遺憾你沒(méi)去聽(tīng)報(bào)告。(that可省)
主語(yǔ)從句應(yīng)注意的幾個(gè)問(wèn)題:
1、that引導(dǎo)的主語(yǔ)從句既可放在句首,也可放在句尾,但在下列情況下that從句不可提前。
。1)在It is said/reported...that結(jié)構(gòu)中:
如:It is reported that a bank was robbed yesterday.
(2)在Ithappened/occurred...結(jié)構(gòu)中:
Ithappenedthattheteacherwasnotintheofficethatday.
。3)含主語(yǔ)從句的復(fù)合句是疑問(wèn)句時(shí):
如:Is it ture that you will give up the job?
2、下面這種情況常用it作形式主語(yǔ)。在It doesn't matter+what/whatever…結(jié)構(gòu)中。
如:It doesn't matter what you say.
3、由what引導(dǎo)的主語(yǔ)從句謂語(yǔ)動(dòng)詞單復(fù)數(shù)問(wèn)題 what引導(dǎo)的主語(yǔ)從句一般按單數(shù)對(duì)待,但是,在實(shí)際使用中究竟按單數(shù)還是按復(fù)數(shù)對(duì)取決于其成分的含義。
如:What we need is more time.
What were left behind were five empty bottles.