2019年高考英语语法必考考点（13）：名词性从句含解析
李仕才
【考点解读】
一、名词性从句的种类
名词性从句包括主语从句、宾语从句、表语从句、同位语从句。
二、引导名词性从句的连接词
1．连接代词：who, whose, whom, what, which有词义，在从句中担任成分，如主语、表语、宾语或定语等。
It has not been decided yet when we will leave. We are worrying about what we should do next.
2．连接副词：when, where, why, how有词义，在从句中担任成分，作状语。 It makes no difference where we shall have the meeting.
Scientists study how human brains work to make computers.(2012·四川高考) 3．连接词： whether, if, as if, if (whether), as if虽有词义，但在从句中不充当任何成分，只起连接作用；that无词义，在从句中也不充当任何成分，只起连接作用，有时可省略。
My suggestion is that we (should) have a discussion about this matter. The question whether we need more time to do the work hasn’t been discussed.
三、that, what引导的名词性从句的区别
引导名词性从句时，that没有词义，在从句中不作任何成分。当从句意义完整，不缺任何成分时，往往选用that；而what引导名词性从句时，意为“什么”或“……的”，在从句中用来作主语、表语或宾语。
What was most important to her, she told me, was her family. (主语从句；what作
主语)
Before the sales start, I make a list of what my kids will need for the coming season. (宾语从句；what作宾语)
As a new graduate, he doesn’t know what it takes to start a business here. (宾语从句；what作宾语)
China is no longer what she used to be. (表语从句；what 作表语)
It never occurred to me that you could succeed in persuading him to change his mind. (主语从句)
One reason for her preference for city life is that she can have easy access to places like shops and restaurants. (表语从句) 【点睛】
(1)that引导主语从句时，常用it作形式主语，常见句型有：
①it＋be＋形容词(如：obvious, true, natural, surprising, good, wonderful, funny, possible, likely, certain, probable, evident, clear, apparent等)＋that从句。 Is it true that the scientist will give us a lecture next week?
②it＋be＋名词(如：no wonder, an honour, a good thing, a pity, no surprise等)＋that从句。
It’s a great pity that it’s probably the last time this will happen.
③it＋be＋过去分词(如：said, reported, thought, estimated, expected, decided, announced, arranged, recognized等)＋that从句。
It is known to all that physical exercises can improve our physical and mental health. 类似句型还有：It cannot be denied that ... /It must be admitted that ... ④it＋动词(如：seem, appear, happen, occur to sb., doesn’t matter, make no difference等)＋that从句。
It doesn’t matter whether you turn right or left at the crossing — both roads lead to the park.
It suddenly occurred to him that he had left his keys in the office. (2)that引导主语从句，置于句首时，that不能省略。
That we are invited to a concert this evening is good news to us.
(3)that引导宾语从句，常可省略。可接that从句作宾语的动词有：see, say, know, imagine,
discover, believe, tell, show, think, consider, be sure, be afraid等。可以接复合宾语的动词有：think, make, consider, find, feel, suppose等，在他们之后，可以用it作形式宾语，而把真正的宾语that从句后置。此时that不可省略。 Do you know (that) he has joined the army?
We consider it necessary that he should improve his pronunciation.
(4)当一个句子有两个或多个并列的宾语从句时，除第一个从句的that外，都不可省略。 He told me (that) the power would be cut off and that I should get ready. (5)引导表语从句：that引导表语从句，不可省略。
My decision is that all of us are to start at 6 o’clock tomorrow.
四、连接词whether/if(是否)的用法
两者都可引导宾语从句，常可互换使用。但以下情况不能互换： 1．宾语从句是否定句时，只用if，不用whether。 I wonder if it doesn’t rain. 2．用if会引起误解，就要用whether。
Please let me know whether you want to go. (此句如果把whether改成if, 可作条件状语从句，因而产生歧义。)
3．宾语从句中的whether与or not直接连用，就不能换成if。 I don’t know whether or not the report is true.
4．介词后的宾语从句要用whether引导。whether可与不定式连用，也可引导主语从句、表语从句、同位语从句，还可引导让步状语从句。
Whether you can make progress in your study depends on whether you try your best. I don’t know whether to laugh or to cry.
Whether you like that gift he gave you, you should express your gratitude. 5．在句首引导主语从句时只能用whether。doubt用于肯定句时，其后的宾语从句用whether或if引导；doubt用于否定句时，其后的从句用that引导。 Whether they will agree with the plan is not clear. I doubt whether/if you have told me the truth.
I don’t doubt that you are the right person for the job.
五、whoever, whatever, whichever, wherever, whenever, however的用法
它们的作用等同于who, what, which, where, when, how, 但语气加强了。这类词引导名词性从句时，不能用no matter＋who/what ...代替。 1．引导主语从句。Whoever did this job must be rewarded.
2．引导宾语从句，充当直接宾语。I’ll give you however much money you need. 3．引导宾语从句，充当间接宾语。She will give whoever needs help a hand. 4．引导介词的宾语从句。You can write about whatever topic you prefer. 5．引导宾语从句，充当宾语补足语。We’ll make him whatever he is fit for.
六、主要考点及突破技巧 主语从句: 1. 主要考点:
1) that引导主语从句时, 常用it作形式主语, 常见的句型: ①It+ be+形容词+ that从句 ②It+ be+名词 (短语)+ that从句
③It+ be+过去分词(said/told/reported/decided等)+ that从句 ④It+ 特殊动词 (seems/ appears/ happens/ matters)+ that从句 2) what与that在引导主语从句时的区别:
what引导主语从句时在从句中充当句子成分, 如主语、宾语、表语, 而that引导从句, 不充当成分。
e.g. What you said yesterday is right. (what引导主语从句, 作said的宾语) That English is important is an undoubted fact. (that引导主语从句, 不作任何成分, 但不可省略)
3) 主语从句若含有“是否”意义, 其引导词只能用whether, 不能用if。 e.g. Whether he will be able to come tomorrow remains a question. 2. 突破技巧:
1) 掌握形式主语的句式及变化，根据句意选取合适连接词, 除that在句子中没有意义, 但不能省略外, 其他连接词均在句中有意义。
2) what, that, which, whether连接主语从句的区别。
宾语从句: 1. 主要考点:
1) 动词find, feel, think, consider, take (认为), make, believe, guess, suppose, assume等后面有宾语补足语时, 且宾语是从句时, 需用it作形式宾语而将that引导的宾语从句后置。
2) 宾语从句的语序为陈述语序; 主句谓语动词用一般现在时, 从句谓语动词可以用各种时态; 主句谓语动词用一般过去时, 从句需用过去的相应时态, 但从句若表示客观真理、规律, 用一般现在时。
e.g. He said that he had been to the space station.
3) 由whether或if引导的宾语从句, 要保持陈述句语序。此外, whether与if在作“是否”讲时, 一般可以换用, 但在下列情况下一般只能用whether, 不用if。 ①引导的从句作介词宾语时。
e.g. Everything depends on whether we have enough money. ②从句中有or或whether or not连用时。 e.g. I wonder whether or not he will come. Tell me whether or not I should invite Nick. ③后接动词不定式时。
e.g. Can you tell me whether to go or to stay? 2. 突破技巧:
1) 把握句意, 选取合适的连接词、时态、语序; 2) 注意whether与if的互换和区别。
表语从句: 1. 考查内容:
1) 表语从句常跟在这些系动词后, 如be, look, remain, seem等。 e.g. That is just what I want.
2) 除常用的连接代词、副词外, as if/ though, because, why等也可以引导宾语从句。 e.g. It looks as if it’s going to rain.
3) 引导表语从句的that不能省略; if不能用于引导表语从句。 e.g. The reason is that he got up late.
(精编)2020年高考英语语法必考考点(13)名词性从句(含解析)
