楊正仁

【摘要】名詞性從句是高中學生學習英語語法的難點，也是高考的熱點之一。名詞性從句包括主語從句、賓語從句、表語從句和同位語從句。本文通過典型例句總結了主語從句的主要用法，同時也分析了主語從句的難點，旨在幫助年輕教師及學生教學語法之參考。

【關鍵詞】連接詞 主語從句 形式主語 難點區(qū)別

眾所周知，引導名詞性從句的連接詞通常有三類，他們用法各不相同，現(xiàn)解釋如下：連接詞that，沒有詞義；不作句子成分；但在主語從句中不能省略；連接詞if ＼whether，詞義“是否”；不作句子成分，不能省略；在主語從句中只用whether；連接代詞what，whatever，which，whichever，who，whoever，whom，whomever，whose 以及連接副詞when，whenever，where，wherever，how，however，why，有詞義；在主語從句中作主語、賓語、表語和狀語；不能省略。

一、主語從句概述

在主從復合句中充當主語的一個句子就叫主語從句，例如：That the earth goes round the sun is well-known to everybody.

Whether she will come to help us has not been known yet.

When we will go to Beijing for visa to America is still a secret.

二、主語從句中的主謂一致

當主語從句作一個主從復合句的主語時，主句的謂語動詞通常用單數(shù)，但what 引導的主語從句中謂語動詞是need，want，require等的時候，主句謂語動詞和表語保持一致，如：

What I am most interested in is American movies.

What I want is a large sum of money.

What I need are a great many books.

三、形式主語

為了避免頭重腳輕，通常用it作形式主語，把主語從句放在后面作真正主語，常用句式有：

1.It + be + 形容詞 + that-從句

It is necessary that everybody should have a healthy diet and exercise regularly.

2.It + be + 過去分詞 + that-從句

It is said that she is going to study abroad after he graduates from Lanzhou University.

3.It + be + 名詞 + that-從句

It is a pity that such an educated and qualified graduate cannot find a job.

4.其他含有it 作形式主義的句式：

It makes no difference who will go to Shanghai for the conference with me.

It remains to be seen whether she will join my research studio.

四、名詞性從句的難點及區(qū)別

1.what引導主語從句時的理解：what 在從句中要充當主語、賓語或表語；what 經常譯為“所…的東西”；what =the thing（s） that，如：

What made him proud was that his students had been admitted to key universities.（作主語）

What they want to do is to continue traveling abroad after retirement.（作賓語）

What she used to be is a secret to us all.（作表語）

2.wh+ever 與 no matter + wh-的用法。引導讓步狀語從句可以換用，引導主語從句只能用wh+ever，如：

Wherever you go and whatever you do，Ill be right here waiting for you.

=No matter where you go and no matter what you do，Ill be right here waiting for you.

Whatever you said at the meeting is very useful and valuable.

Whoever leaves the office last，please close the window.

=No matter who leaves the office last，please close the window.

Whoever leaves the office last must close the window.

參考文獻：

[1]張道真.實用英語語法[M].外語教學與研究出版社.2002.

[2]薄冰.英語語法[M].開明出版社.1998.