【导语】“西凉河葛三叔”通过精心收集，向本站投稿了7篇主语从句语法详解，下面是小编收集整理后的主语从句语法详解，仅供参考，希望能够帮助到大家。
- 目录
篇1：主语从句语法详解
▼主语从句的概念与类型
主语从句在复合句中作主句的主语,引导主语从句的词有从属连词that, whether以及连接代词who, what,which, whoever, whatever, whichever和连接副词when, where, why, how等.
例如:
That she was chosen made us very happy.
她当选了使我们很高兴.
What caused the accident is a completemystery.
是什么导致了这次事故还完全是一个谜.
Whether she will come or not is still a question.
她是否来还是一个问题.
Which team will win the match is stillunknown.
哪个队会赢得这场比赛还不知道.
Whoever comes to the party will receive apresent.
参加聚会的每一个人都将收到一份礼物.
When they will start has not been decidedyet.
他们何时出发还没决定.
注意:上述例句中的主语从句都是放在句首,但有时为了使句子结构平衡,避免“头重脚轻”,常用it作形式主语,而把从句放在后面.
例如:
It is a pity that she has made such amistake.
她犯了这样一个错误,真是遗憾.
It depends on the climate whether they aregoing shopping today.
他们是否今天去购物还得看天气情况.
这样就构成了下面一些常用句型:
1)It is + adj. / n. +从句
It is a pity/shame that...遗憾的是……
It is possible that...很可能……
It is unlikely that...不可能……
2)It +不及物动词+从句
It seems/appears that...似乎……
It happened that...碰巧……
3)It + be +过去分词+从句
It is said that...据说……
It is known to all that...众所周知……
It is reported that...据报道……
It is believed that...据信……;人们相信……
It is suggested that...有人建议……
It must be pointed out that...必须指出……
It has been proved that...已证明…….
例如:
It is believed that at least a score ofbuildings were damaged or destroyed.
据信,至少有二十座楼房遭到破坏或彻底毁掉.
It is suggested that the meeting should beput off.
有人建议会议延期召开.
It's reported that three people were killedin the accident and five were hurt badly.
据报道,事故中三人丧生,五人重伤.
It is known to all that Taiwan is aninseparable part of China.
众所周知,台湾是中国不可分割的一部分.
▼主语从句的语法
<例句>
It's certain that prices will go up.
物价肯定要上涨的。
<语法分析>
主语从句可以由that引导，此外还可由连接代词或连接副词引导，关系代词what或whatever也可引导主语从句。由that引导的主语从句是用的最多的一种主语从句，有时为了强调，可以把从句放在句首，而绝大部分主语从句则借助先行主语放到句子后部去。
<触类旁通>
(1)That she hasn't phoned is odd.
她没有来电话很奇怪。
语法分析：that引导的主语从句。
(2)That he was chosen made a tremendous stir in his village.
他被选中在他村子里引起很大轰动。
语法分析：有时为了强调或谓语较长时，可以把从句放在句首。
(3)It is natural that they should have different views.
他们有不同观点是很自然的。
语法分析：it+be+形容词或名词+that从句。
(4)It happened that he wasn't in that day.
恰巧他那天不在。
语法分析：it+动词+that从句。
(5)It's doubtful whether we'll be able to come.
我们是否能来还是个疑问。
语法分析：连接代词或连接副词可引导主语从句。
(6)What will be,will be.
该发生的事，总会发生。
语法分析：关系代词型what也可引导主语从句。
<巩固练习>
(1)______ he is still alive is a consolation.
(2)It's strange ______ she knows nothing about it.
(3)It may be ______ you'll prove yourself the most suitable.
(4)______ is to be sent there hasn't been decided.
(5)It was clear enough ______ she meant.
(6)______ is over is over.
(7)______ he says goes.
(8)______ she saw made her tremble.
<参考答案>
(1)That (2)that (3)that (4)What (5)what (6)What (7)Whatever (8)What
▼主语从句的注意问题
1)引导词that与what
what既有引导主语从句的作用,同时又在从句中作句子成分(主语、宾语、表语等).这时what相当于all that/everything that...,常译成“所……的(东西、事情、话等.)”;而that只起连接作用,本身无实际意义,在从句中也不担当任何句子成分.但that引导的主语从句放在句首时,不能省略that.
例如:
What is done can't be undone.
(谚语)已成定局,无可挽回.
What we can't get seems better than what wehave.
我们得不到的东西似乎比已得到的要好. That we should work out a plan to deal with the present serioussituation is important.
我们应该制定一项计划来应付目前严峻的形势,这一点非常重要.
That a new teacher will come to teach usgeography is true.
一位新老师将来教我们地理,这是真的.
▼主语从句的语气
在It is necessary / natural/ important / strange...+ that-clause
这类句型里,that所引导的主语从句中谓语动词用“should+原形”,表虚似语气.
例如:
It is necessary that the problem should besettled at once.
这个问题必须马上解决.
It's strange that he should have gone awaywithout telling us.
他竟然没向我们说一声就走了,真是奇怪.
巩固练习
15. It isnecessary that a college student _______ at least a foreign language.
A. masters B.should master C. mastered D. will master
四、以it作形式主语的主语从句与强调句型的区别
“It be + adj./n. + that-clause”与强调句型均有It be...that...之类的语言标志,但不同的是:①前者中的that从句是主语从句.若删掉其中的It be和that,则剩余部分不论结构还是语意都不能成为一个句子;但若将后者中的It be和that去掉,则剩余部分的结构和语意仍能构成一个完整的句子.②强调句型译为汉语时可加上“正是……”或“就是……”之类的字眼,而主语从句则不可以.
请比较下面两个句子:
It is surprising that Mary should have wonfirst place.
令人惊奇的是玛莉竟然获得了第一名. It is Mary that has won first place.
正是玛莉得了第一名.
第一句话中的It是形式主语,that引导的是主语从句.句中的It is和that无法删除,一旦删除句子就不成立.
第二句是强调句型,其中的It is和that可以去掉,因为没有It is和that句子仍然很通顺.
篇2：名词性主语从句语法详解
(1)名词性从句(归属于名词类)：
主语从句
表语从句
宾语从句
同位语从句
(2)形容词性从句(起描绘名词的修饰作用，归属于形容词类)：
定语从句
(3)副词性从句(起描绘谓语动词的修饰作用，归属于副词类)：
状语从句
1.名词性从句
1.1主语从句——一般们于句子的开头，以从属连词引导。
•连接主语从句的连词
纯连词：that(不有词义，只起连接作用，在从句中不充当成分)
whether
连接副词：when, where, how, why
连接代词：what, whatever, who, whoever, which
That Jack got an A for his physics is a surprise.
杰克的物理得了优秀真是令人惊喜的。
That July went to New York is no news now.
朱莉去纽约一事可不是什么新闻了。
注意，此类主语从句通常必成以下形式，显得更平衡自然一些：
It is surprise that Jack got an A for hisphysics.
It is no news now that July went to NewYork.
此类从句中的that是不能省略的，因为省去that后就不看出是从句了。
Whether she agrees or not is nothing to me.
她是否同意对我毫无影响。
Whether we come or not depends on the weather.
我们是否来取决于天气。
此类主语从句中的whether既起连接作用，又有意思，不能省略。
特别需要注意的是：
用whether引导的主语从句，不能使用if代替：
×If she agrees or no is nothing to me.
×If we come or not depends on the wether.
When we set out is not decided yet.
我们何时出发还没定下来呢。
How she succeeded remains a secret.
他怎么成功的仍然是一个秘密。
Where Bob chooses to stay is up to him.
鲍勃选择在哪里居住由他自己决定。
What the teacher stressed will be in the exam paper.
老师强调的内容会出现在考卷中。
Who is the new teacher matters a lot.
谁当新教师关系可大了。
本文载自微信公众号“英语语法学习”。本文已获转载授权，版权归作者所有，如需转载，请联系原微信公众号“英语语法学习”。
公众号：英语语法学习
篇3：语法讲座之主语从句
基本概念
1．定义：用作主语的从句叫做主语从句。
2．构成：关联词+简单句
3．引导主语从句的关联词有三类：
(1) 从属连词that。 如：That they were in truth sisters was clear from the facial resemblance between them.
很明显，她们确是亲姐妹，她们的脸型很相似。
(2) 从属连词whether。如：
Whether hell come here isnt clear. 他是否会来这里还不清楚。
(3) 连接代词who, whom, whose, what, which, whoever, whatever, whichever
连接副词 where, when, how, why。如：
What she did is not yet known. 她干了什么尚不清楚。
How this happened is not clear to anyone. 这事怎样发生的，谁也不清楚。
Whoever comes is welcome. 不论谁来都欢迎。
Wherever you are is my home ---- my only home. 你所在的任何地方就是我的家----我唯一的家。
重点疑难
1．主语从句能用it作形式上的主语。常以it作形式主语的句型有：
A.It+be+形容词(obvious, true, natural, surprising, good, wonderful, funny, possible, likely, certain, probable, etc.)+that从句。如：
It is certain that she will do well in her exam. 毫无疑问她考试成绩会很好。
It is probable that he told her everything. 很可能他把一切都告诉她了。
B.It+be+名词词组(no wonder, an honour, a good thing, a pity, no surprise, etc.)+that从句。如：
Its a pity that we cant go. 很遗憾我们不能去。
Its no surprise that our team should have won the game. 我们没赢这场比赛真意外。
C.It+be+过去分词(said, reported, thought, expected, decided, announced, arranged, etc.)+that从句。如：
It is said that Mr. Green has arrived in Beijing. 据说格林先生已经到了北京。
It is reported that China has sent another man-made earth satellite into orbit.
据报道中国又成功地发射了一颗人造地球卫星。
D.It+seem, happen等不及物动词及短语+that从句。如：
It seems that Alice is not coming to the party at all. Alice似乎不来参加晚会。
It happened that I was out that day. 碰巧我那天外出了。
E.It+doesnt matter (makes no difference, etc.)+连接代词或连接副词引起的主语从句。如：
It doesnt matter whether she will come or not. 她是否来这无关紧要。
It makes no difference where we shall have the meeting. 我们在哪里开会毫无区别。
F.当that引导的主语从句出现在疑问句中时，要以it作形式主语，而把主语从句后置。如：
Is it true that the scientist will give us a lecture next week? 下周那位科学家将给我们作报告是真的吗？
Does it matter much that they will not come tomorrow? 他们明天不来很要紧吗？
G.当主语从句出现在感叹句中时，要以it作形式主语，而把主语从句后置。如：
How strange it is that the children are so quiet! 孩子们这么安静真奇怪！
2．注意连接代词whoever, whatever, whichever等引导主语从句的含义
Whoever comes will be welcome. (whoever=the person who) 来的人将受到欢迎。
Whatever he did was right. (whatever=the thing that) 他所做的事情是正确的。
Whichever of you comes in will receive a prize. (whichever=anyone of you who) 你们当中不论哪个进来将会得到奖励。
篇4：同位语从句语法详解
什么是同位语
例如：王思聪，“国民老公”，被称为“娱乐圈纪委书记”。
王思聪就是“国民老公”。
“国民老公”就是王思聪。
“国民老公”就是王思聪的同位语。
同位语的特征
引导词几乎都是抽象名词，news，possibility(可能性)，chance(可能性)，word(消息)，phenomenon(现象)， fact，evidence(证据)，belief(信念)等。
The fact that the earth moves around the sun is known to us.
关联词有that，whether，why，when，how等等，关联词的选用由句子意思决定：缺什么选什么，意思完整选用that。
I have no idea whether he will come back tomorrow.
同位语的判断方法
方法：在引导词和同位语从句加上“是”能够成为一个完整的句子就是同位语从句。
The fact that the earth moves around the sun is known to us.
The fact is that the earth moves around the sun.
事实是地球绕着太阳转。
本文载自微信公众号“英语语法学习”。本文已获转载授权，版权归作者所有，如需转载，请联系原微信公众号“英语语法学习”。
公众号：英语语法学习
篇5：考研语法定语从句详解
一、定语从句的构成：先行词(所修饰的名词)+关系代词/关系副词(从属连词)+从句
二、定语从句的类型：根据从属连词的不同可以将定语从句分为三种类型：关系代词引导的定语从句，关系副词引导的定语从句，和as/which引导的非限制性定语从句。
1. 关系代词引导的定语从句
在这一类从句中需要注意的是关系代词在句子中所起的作用。首先，关系代词连接主句和从句;其次关系代词指代所修饰的先行词;最后关系代词往往在从句中做主语或者宾语，且做主语时关系代词不能省略，做宾语时可以省略。
例1：He who laughs last laughs best. (笑到最后的人笑得最美。)
分析：who引导定语从句修饰主句的主语he，且在从句中做主语，不能省略。
例2：He is collecting authentic material which can prove his argument. (他正在收集确凿的证据以证明他的观点。)
分析：that引导定语从句修饰名词material，且在从句中做主语，不能省略。
例3：The house (which) we bought last month is very beautiful. (我们上周买的这套房子很漂亮。)
分析：which引导定语从句修饰名词house，且在从句中做宾语，可以省略。
例4：The girl whose mother is a doctor is waiting for you outside. (妈妈是个医生的那个女孩在外面等你。)
分析：whose引导定语从句修饰表示人的名词the girl，且在从句中做主语，不可以省略。
2. 关系副词引导的定语从句
前三种关系副词在考研英语中出镜率比较高，最后一种不太常见，容易被考生忽略。关系副词在意义上常常相当于一个“介词+which”的结构。
例1：The commentator must know the value of silence and how to use it at those moments when the pictures speak for themselves. (播音员必须懂得沉默的价值，懂得在画面不需要解释说明的时刻如何利用沉默。)
分析：when引导定语从句修饰表示时间的名词moments，在从句中做时间状语。
例2：When the work is well done, a climate of accident-free operation is established where time lose due to injuries is kept at a minimum. (工作完成后，一种无事故操作的环境被建立起来，在这种环境中，由于伤害造成的时间损失被保持在最低水平。)
分析：where引导定语从句修饰表示场合的名词climate，在从句中做地点状语。
例3：Do you know the reason why there are heat losses in a steam engine? (你知道蒸汽机中存在热损耗的原因吗?)
分析：why引导定语从句修饰名词reason，在从句中做原因状语。
例4：Teaching has traditionally been the method whereby many intellectuals earn their living. (按照传统，教书是许多知识分子借以谋生的手段。)
3. as/which引导的非限制性定语从句
As/which引导的非限制性定语从句不仅可以修饰某个词语，而且可以修饰整个主句。而as引导的从句位置灵活，既可以位于句首，也可以位于句尾或者句中。且有些表达已经固定下来，如as is known to all 众所周知;as is often the case 情况往往如此。相比而言，which的位置就比较受限制，通常位于句末。
例1：Stratford-on-Avon, as we all know, has only one industry----William Shakespeare. (众所周知，艾文河畔的斯特拉特福镇，只有一种产业――威廉.莎士比亚。)
分析：as引导定语从句，使用了其固定表达。
例2：She is quite considerate and kind, which her younger sister never is. (她非常善良、体贴，而她妹妹却从不这样。)
分析：which引导非限制性定语从句，指代前面整个句子。
篇6：大学英语四级语法精要：主语从句之三
主语从句之三：
由连接代词或连接副词(或whether)引起的主语从句:
这类主语从句, 也可以放到句子后部去, 前面用it做形式上的主语.
when we shall have our sports meet is still a question.
it is still a question when we shall have our sports meet.
whether he will join us won’t make too much difference.
it won’t make too much difference whether he will join us.
篇7：that做主语引导什么从句
1、在suggest，order等表示命令、请求、建议等动词后的宾语从句中，不能省。
2、由and或but所连接的两个引导的'宾语从句时，第一个从句中的that可以省，第二个从句中的that不能省。
辨析：
that， which：
that和which都可引导定语从句，但以下情况引导定语从句的关系代词只能用that不能用which：
1、当先行词是all， everything， nothing， anything， little等不定代词，或被first， last， only， few， much， some， any， no等词修饰时，应该用关系代词that，不用which。
2、当先行词为形容词最高级所修饰时，关系代词用that不用which。
3、当并列的两个先行词分别表示人和物时，要用关系代词that而不用which。
4、在强调句型“It is．．．that．．．”中，只能用that，不能用which。
★ 英文歌语法
★ 语文语法
★ 虚拟语气语法
★ 汉语语法
主语从句语法详解（通用7篇）
