2021-2022学年人教版高中英语必修三教学案：Unit 4 Section 3 Word版含答案

Section_ⅢGrammar—主语从句

语法图解

探究发觉

①What it was to become was uncertain until between 4.5 and 3.8 billion years ago when the dust settled into a solid globe.

②The earth became so violent that it was not clear whether the shape would last or not.

③What is even more important is that as the earth cooled down, water began to appear on its surface.

④It was not immediately obvious that water was to be fundamental to the development oflife.

⑤What many scientists believe is that the continued presence of water allowed the earth to dissolve harmful gases and acids into the oceans and seas.

⑥So whether life will continue on the earth for millions of years to come will depend on whether this problem can be solved.

[我的发觉]

(1)以上黑体部分在句中作主语。

(2)①句中的what在从句中作表语，但⑤句中的what在从句中作宾语；③句中的what在从句中作主语。

(3)②⑥句中的whether意为：是否。

(4)④句中it是形式主语，真正的主语是后面that引导的从句。

一、定义

在主从复合句中充当主语的从句即为主语从句。

What made people excited was that the solar ship had completed around-the-world trip.

让人们感动的是太阳能船已完成了环游世界的旅行。

It worried the woman that her son was always playing computer games.

儿子始终在玩电脑玩耍，这让这个女人很担忧。

二、主语从句的连接词及其句法功能

1．连接词that和whether/if

(1)that在从句中不充当任何句子成分，本身无任何意义，只起连接作用，但不行省略。

That she survived the accident is a miracle.

她在事故中幸免于难简直是奇迹。

(2)whether/if在从句中不充当任何句子成分，起连接作用，意为“是否”，不行省略。

Whether the plan will be carried out is still unknown.

＝It is still unknown if/whether the plan will be carried out.

这个方案是否会实施还不知道。

[名师点津]whether引导的主语从句既可放在句首也可放在句尾，但if引导的主语从句只能放在句尾，前面需用it作形式主语。

[即时演练1]补全句子

①That_she_could_come_to_help_us made us very happy.

她能来挂念我们使我们很兴奋。

②Whether_she_is_coming_or_not doesn't matter too much.

她来不来都无关紧要。

2．连接代词(who, whose, whom, what, which, whichever, whoever, whomever, whatever等)

连接代词引导主语从句，在从句中可以作主语、宾语、表语或定语。

Whichever (of you) comes in first will receive a prize.

无论(你们)谁先到都可以得奖。

Who will go to the concert is not known.

不知道谁会去听音乐会。

Whatever you do in your spare time should do no harm to others.

无论你在业余时间做什么都不应当损害其他人。

[名师点津]who 引导的主语从句表示一件“事情”，而whoever引导的主语从句指“人”。

3．连接副词(when, where, how, why等)

连接副词引导主语从句并在从句中作状语。

How this happened is not clear to anyone.

这件事怎样发生的，谁也不清楚。

When we will have a meeting is an important question.

我们何时进行会议是个重要的问题。

Where I spend my summer is no business of yours.

我在哪里过暑假不关你的事。

[名师点津]名词性从句引导词的确定步骤：

(1)分析句式结构，明确名词性从句在句中的功能；

(2)明确名词性从句所表达的意义；

(3)明确名词性从句中所需要的成分及意义；

(4)确定从句的引导词。