2018年公共英語四級(jí)重點(diǎn)語法資料：表語從句

　　表語從句

　　1、表語從句概述

　　表語從句在復(fù)合句中作主語的表語。一般放在主句的謂語動(dòng)詞(聯(lián)系動(dòng)詞)之后，引導(dǎo)表語從句的詞有連詞that, whether, as if;代詞who, what, which;副詞when, where, how, why等，如：

　　The trouble is that she has lost his address. 麻煩在于她弄丟了他的地址。

　　The question is whether it is worth doing. 問題在于是否值得做。

　　It looked as if it was going to snow. 看起來似乎要下雪。

　　That is what he is worried about. 那就是他所擔(dān)憂的。

　　That is where he was born.那兒是他出生的地方。

　　This is how she did it. 這就是他如何做這件事的。

　　That is why he was late. 那便是他為何遲到了。

　　2、that引導(dǎo)的表語從句

　　當(dāng)表語從句為陳述句的語氣時(shí)，用that來引導(dǎo)，that無任何義，不充當(dāng)任何句子成分，如：

　　The fact is that the child is lying. 事實(shí)是那個(gè)小孩在說謊。

　　The trouble is that we are short of money. 問題在于我們?nèi)卞X。

　　The reason is that we can’t get there on time. 原因在于我們不能按時(shí)到達(dá)那里。

　　3、whether引導(dǎo)的表語從句

　　當(dāng)表語從句為不確定的語氣時(shí)，用whether來引導(dǎo)，此時(shí)通常不可用if代替whether，如：

　　The question is whether people will buy it. 問題在于人們是否會(huì)買它。

　　What I want to know is whether I should to there. 我想要知道的是我是否應(yīng)該去那里。

　　4、wh-疑問詞引導(dǎo)的表語從句

　　當(dāng)表語從句為疑問的語氣時(shí)，用wh-疑問句來引導(dǎo)，要注意表語從句的語序要用陳述句的語序，如：

　　The question is where we should go. 問題是我們應(yīng)該去哪兒。

　　That is why he was late. 那是他為什么遲到了

　　5、as if/ though引導(dǎo)的表語從句

　　He looks as if he were angry. 他看起來似乎非常生氣。