主语从句的基本用法
[观察例句]
That you are coming to London is the best news I have heard this long time.
你将要来伦敦是这么长时间以来我听到的最好的消息。
Whether it will do us harm remains to be seen.
它是否对我们有害还有待观察。
What I have seen today has made a very deep impression on me.
今天我的所见所闻给我留下了非常深刻的印象。
Whoever breaks this law deserves a fine.
触犯本法者应予以罚款。
Whichever(of you)comes in first will receive a prize.
(你们中)谁先进来谁就会得奖。
When we will have a meeting is an important question.
我们何时举行一次会议是个重要的问题。
Where we shall do the test is still under discussion.
我们在什么地方做这个测试还在讨论中。
主语从句的引导词
[归纳用法]
| 类别 | 例词 | 说明 |
| 从属连词 | that, whether | 两者在从句中均不作成分，只起连接作用；that无实义，whether表示“是否”。 |
| 连接代词 | who, what, which, whoever, whatever等 | 在从句中作主语、宾语、表语、定语等成分。 |
| 连接副词 | when, where, how, why等 | 在从句中作时间、地点、方式、原因状语等成分。 |
[注意] 主语从句中连接词的选择技巧
(1)根据连接词在从句中所作的语法成分。
(2)根据连接词在从句中的意义。
[即学即练1]——用whether, that, whoever填空
①_____________ she became an artist may have been due to her father’s influence.
②_____________ we will hold a party in the open air tomorrow depends on the weather.
③Every year, _____________ makes the most beautiful kite will win a prize in the Kite Festival.
It作形式主语
[观察例句]
It’s possible that he has been to Beijing. 他有可能去过北京。
It’s a pity that you didn’t attend the meeting. 你没参加这次会议太可惜了。
It seems that it is going to rain. 看起来好像要下雨。
It is important that he should know about this. 他应该知道此事是重要的。
It is suggested that the meeting be put off. 有人建议会议延期召开。
[归纳用法]
为保持句子平衡，常把主语从句后置，而用形式主语it代替。it作形式主语时常用于以下句型：
| 句型 | 说明 |
| It＋系动词＋形容词＋主语从句 | 常用于此句型的形容词有important, (un)likely，possible, necessary, natural, wrong等。 |
| It＋系动词＋名词＋主语从句 | 常用于此句型的名词有fact，idea，honour，question，pity等。 |
| It＋系动词＋过去分词＋主语从句 | 常用于此句型的过去分词，有known，proved，said，decided，suggested，thought等。 |
| It＋不及物动词＋主语从句 | 常用于此句型的动词有appear，happen，seem，occur，matter等。 |
[注意]
(1)在“It＋be＋过去分词＋主语从句”结构中，过去分词若为suggested/ordered/required/advised等，主语从句中的谓语用“(should)do”。
(2)在“It＋be＋形容词＋主语从句”结构中，若形容词为important/necessary/strange等，主语从句中的谓语用“(should)do”。
[即学即练2]——完成句子
①很可惜你不能来参加我的生日聚会。
_____________ that you can’t attend my birthday party.
②有人建议这位老人到乡村休息一下。
_____________ that the old man should go to the countryside to have a rest.
③在我看来你好像不赞成这个计划。
_____________ that you disagree with the plan.
注意事项
1．从句要用陈述语序
How he succeeded is still a puzzle. 他是如何成功的仍然是个谜。
2．主谓一致
(1)从句作主语时，主句的谓语一般用单数形式。
Where he will get a job after graduation has puzzled him much.
毕业后到哪儿找一份工作使他很困惑。
[注意] what引导主语从句时，有时主句谓语动词应与主句中作表语的名词保持一致。
What the school needs most are books. 这所学校最需要的是书。
(2)如果由and连接两个或两个以上的主语从句作主语时，谓语动词用复数；由两个或多个连接词引导一个主语从句时，谓语动词用单数。
When they will start and where they will go have not been decided yet.
他们将在什么时候动身以及要去哪里还没定下来。
When and where they will hold the meeting is not clear.
他们何时何地召开会议还不清楚。
[即学即练3]——单句语法填空
①When we will set off _____________(be)still under discussion.
②When and where the meeting will be held _____________(have)not been decided.
Mindmap解析
Exercises
Ⅰ.单句语法填空
1．It is often the case _____________ anything is possible for those who hang on to hope.
2．Your support is important to our work. _____________ you can do helps.
3．_____________ Li Bai, a great Chinese poet, was born is known to the public, but some won’t accept it.
4．_____________ we understand things has a lot to do with what we feel.
5．Exactly _____________ the potato was introduced into Europe is uncertain, but it was probably around 1565.
6．_____________ the delayed flight will take off depends much on the weather.
7．I think _____________ impresses me about his painting is the colours he uses.
8．Some people believe _____________ has happened before or is happening now will repeat itself in the future.
9．_____________ makes the book so extraordinary is the creative imagination of the writer.
10．_____________ you said at the meeting describes a bright future for the company.
Ⅱ.完成句子
1．有人命令操场建设下周完成。
It is ordered that the construction of the sports ground __________________________．
2．现在她正在买的东西是一些杂志。
_______________________________________ are some magazines.
3．很明显刚刚有人来拜访过他。
It is clear _______________________________________．
4．这个地区的争执(dispute)何时结束让很多人困惑。
_______________________________________ puzzles many people.
5．她没有出席婚礼宴会的原因是她头痛。
_______________________________________ is that she had a headache.