下面将以最简单的图文形式讲清楚什么是“主从句”、什么是“单复句”、什么是“定语从句、名词从句、状语从句”。
单句——拥有一套“主谓结构”（一个时间）；
复句——拥有两套以上“主谓结构”（两个以上时间）；
主句——可以独立存在的单句
从句——不可以独立存在的单句（必须寄生在主句身体里）
引导词——链接从句到主句身体的手铐（从句身份标志）
一、名词性从句——从句占位
主语从句： （主-谓-宾）-谓-宾——占主语位
That he finished writing the composition in such a short time surprised us all.
他在如此短的时间内写完作文使我们十分惊讶。
宾语从句：主-谓-（主-谓-宾）——占宾语位
I don't know if there will be a bus any more.
我不知道是否还会有公交车.
宾语从句：主-谓-宾-（主-谓-宾）——占第二宾语位
He told me that he would go to the college the next year.
他告诉我他下一年上大学.
二、定语从句（形容词性从句）——从句不占位，而是插入
主语部分：主（主-谓-宾）-谓-宾——插入主语里的定语从句
The first English book that I read was "The Prince and the Pauper" by Mark Twain.
我读的第一本书是马克·吐温写的《王子与贫儿》。
宾语部分：主-谓-宾（主-谓-宾）——插入宾语里的定语从句
I'll never forget the days I spent in the countryside.
我永远不会忘记我在农村度过的日子。
宾语部分：主-谓-宾-宾（主-谓-宾）——插入第二宾语里的定语从句
Someone sent me a book from Seoul that Jack Nicklaus had written called "My Way, " which taught me how to grip the clubs and how to swing.
有人从首尔给我寄来了一本杰克·尼克劳斯(Jack Nicklaus)写的《我的路》(My Way)，这本书教会了我如何握杆和挥杆。
三、状语从句
（主-谓-宾），主-谓-宾
When I met the Gills, I had been gardening for nearly ten years.
我结识吉尔一家时，我已经几乎做了十年的园艺。
主-谓-宾（主-谓-宾）
How can I love myself when I look like this?
既然我这么一副样子，我怎么能爱我自己？
英语句子的结构很简单，在任何情况下一个句子（非并列句）只有一个主谓结构。只是在这个主谓结构的基础上可以综合使用以上三种从句，同时结合三种非谓语动词短语进一步修饰细化增添诸多细节，在配合主句和从句谓语动词各种时态变化（主动、被动、真实、虚拟）从而导致句子变得复杂起来。
但是只要你能够抓住主句的主谓结构，那么在复杂的句子都可以被清晰的解析理解。
本文作者谢瑞，著有《英语思维：解密英语语法的原理》一书和《英语思维：十课建立完美语法体系》系列视频课程，欢迎转载，转载请注明出处。
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第1个回答 2019-12-23
从句是指用于复合句中担当某个句子成分的主谓结构。虽说从句自身的句子结构是完整的， 但是它不能视为独立的句子，因为它离开了主语就无法独立、完整地表达意思。按其所能表达的意义而言,它相当于一个词或是一个词组.例如： 1) Because they talk at home while the television is on , many people think they can talk at movies as well . （状语从句）许多人在家里是边看电视边谈话，所以他们认为在电影院也可以如此。 2) Whether he comes or not doesn't make any difference to me . （主语从句） 他来与不来对我都一样。 3)There is disagreement among economists about what money is and how money is measured（宾语从句）什么是货币以及怎样计量货币经济学家之间存有分歧。 4） China is not what it used to be . （表语从句）中国不是它过去的样子了。 5） Is there any proof that the food of plant differs from that of animals ? （同位语从句）有没有什么证据说明植物性食品不同于动物性食品？ 6) Taxes consist of money that people pay to support their government . （定语从句） 税款是人们支持政府而交的钱。 如果将上面的复合句中所有的从句都独立出来，那将是这样的： 1） Because they talk at home while the television is on 2） Whether he comes or not 3） what money is and how money is measured 4） what it used to be 5） that the food of plant differs from that of animals 6） that people pay to support their government 我们很容易看出，上面的所有这些句子既不是陈述句、疑问句，也不是祁使句，更不是感叹句。也就是说，它们不是独立的句子；也只有在附属于主句后才能获得意义如下：1）因为许多人在家里是边看电视边谈话 2）他来与不来 3)什么是货币以及怎样计量货币 4)它过去的样子5)植物性食品不同于动物性食品6）人们支持政府而交的上面的这些句子在我们中文里如同是人们常说的"半截话"；在英文中也就是个"词或词组"了。 B. 我们虽然说过，从句自身的句子结构基本是完整的，但是它不同于"独立句子"的是--每个从句的最前面都好象"戴了顶帽子"即：从属关系词。由此可以看出，从句的另一个特点是：从属关系词总是立于从句之首. C. 从句的再一个特点是:一般说来（除少数倒装的情况外），从句中的语序应该是正常语序。 D. 关于从句种类的划分有两种方法：按从句的词性划分和按从句的句子功能划分。如果按从句的词性划分，从句可分为三种：名词从句、形容词从句和副词从句。如果按从句的句子功能划分（也就是按从句在句子中所担任的成分来划分），从句可分为：主语从句、宾语从句、 表语从句、同位语从句、定语从句和状语从句。其实，这两种划分从句的方法在逻辑上是一致的.我们知道，能在句子里充当主语、宾语、表语和同位语的往往是名词、代词等，所以名词从句涵盖了主语从句、宾语从句、表语从句和同位语从句。形容词和副词常分别在句中担当定语和状语，所以，形容词从句和副词从句其实分别是定语从句和状语从句。 名词从句名词从句在句中是一个相当于名词的主谓结构。我们在前面说过，名词从句含盖了主语从句、宾语从句、表语从句和同位语从句。连接这些从句与主句的关系词主要有三类： 1.从属连词：that（无有词义） , whether（是否） ,if （是否） 2.关系代词：who（谁，主格） , whom（谁，宾格）,whose谁的，所有格） , what（什么）,which（哪个，哪些） 3.关系副词：when（什么时候） where（什么地方）why（为什么） , how（怎样） 名词从句中的从属连词在从句里不担任任何成分，只起连接的作用；而关系代词和关系副词不仅仅是起连接的作用，而且还在从句里担任一定的成分;关系代词常在从句中担任主语、宾语或表语等成分；关系副词常在从句中担任状语。另外，在使用上面的这些关系词时，有几个问题值得我们注意：首先，只能用whether而不能用if的情况. 1）引导主语从句，例如： Whether we'll make a loan for the project has not been decided .（正确）我们是否要为这个项目还没有定下来。 OR: It has not been decided whether we'll make a loan for the project . （正确） If we'll make a loan for the project has not been decided .（错误） OR: It has not been decided if we'll make a loan for the project . （错误） 2）作介词的宾语，例如： I have no idea about whether I can raise the money for buying a car . （正确）我不知道我是否能为买车筹措到资金。 I have no idea about if I can raise the money for buying a car . （错误） 3）后接不定式 ，例如： He didn't know whether to go all himself first or wait for her here.(正确)他不知道是他自己先去还是在这儿等她。 He didn't know if to go all himself or wait for her here . （错误） 4）后接or not ，例如： We wonder whether they'll come in time or not.(正确) 我们担心他们会不会准时到。 We wonder if they'll come in time or not . （错误）其次，what引导的名词从句表达的意思是"……所……的"。这个"所怎么的"定义根据"从句谓语的动作意义"而定。例如： I don't understand what you said.我不理解你所说的话。 What he needs is to practice more.他所需要的是勤于练习。 Money is what she is really after.金钱是她所真正追求的东西。 People have different ideas about what happiness means . 人们对于幸福的含义有不同见解。最后，要了解 -ever = no matter ，用于表示强调，意为"无论……"。也就是说： whatever = no matter what（无论什么） whoever = no matter who（无论谁） whichever = no matter which（无论那个） whenever =no matter when （无论何时） wherever = no matter where（无论何地） however = no matter how （无论怎样） A 主语从句用作主语的主谓结构称之为主语从句。例如： Whether he'll come or not remains a question . 他是否会来依然是一个问题。 Whoever says that is not allowed .无论谁这样说都是不允许的。 That she reads English aloud every morning helps her a lot in the improvement of her English study . 她每天早晨朗读英文对提高她的英语学习起了很大的作用。 要点提示在使用主语从句中，有几个问题值得我们注意： 1）尽管主从连词that在主语从句中没有任何意义,但一般不能省略。 That there is no elevator in the building is the critical inconvenience .这幢楼里没有电梯是极大的不便之处。 It is necessary (that) he have his further study incollege.(当主语从句在后面时，连词that可以省去)他在大学进一步深造是完全必要的。 2）为了保持句子平衡或在正式文体中,常用先行It代替主语从句而将主语从句置于句末。 It remains a question Whether he'll come or not . 他是否会来，依然是一个问题。 It is not allowed Whoever says that. 无论谁这样说都是不允许的。 3）在It + be +形容词/ 名词 + that从句的结构中，由于某些形容词/ 名词的原因，that从句中的谓语动词要用虚拟式。这类形容词/ 名词常见的有： essential（绝对必要的）, important（重要的）, advisable（明智的）, desirable（希望能够的）, imperative（必须的）, natural（自然的）, necessary必要的）, regretful（遗憾的）, strange（奇怪的）, proper（适当的）, urgent（紧急的）, duty（义务、责任）, a pity （遗憾）, no wonder（难怪）, a regret（遗憾）。例如： It is strange that he ( should ) say so . 他居然会这样说，真是奇怪。 It is a great pity that you ( should ) think so . 他居然会这样想，真是一件憾事。 It is natural that a bird ( should ) rest in trees . 鸟在树上安歇是很自然的。 It is a wonder that he should have passed the exam. 他这次考试居然会及格，真是个奇迹。 4）以what引导的主语从句常用于句首表示强调。 What they need now is financial aid . 他们现在所需要的是经济援助。 What she thinks of me doesn't mean much to me . 她怎么样看我，对我来说无所谓。 What you have said hurt her a lot .你所说的话对她伤害很大。 B 宾语从句用作谓语动词、介词以及非谓语动词形式的宾语的主谓结构称之为宾语从句。也就是说,只要是用一个主谓结构去充当宾语，那么这个主谓结构就称为宾语从句。 例如： I believe that he will find a job in that publisher .（作谓语动词的宾语）我相信，他一定会在那家出版社找到工作。 He laughed at what they said . （作介词的宾语）她对他们说的话，一笑置之。 要点提示在使用宾语从句中，有几个问题值得我们注意： 1）宾语从句与主句的时态一致性问题这种一致性的要求,只有当主句的谓语动词用于"过去时区"的时候才存在。凡是在"过去时区"内的各种不同时态都在其中。另外，这种一致性只要求宾语从句的谓语动词也用于"过去时区"即可，至于用什么样具体的时态就要依从句的需要而定了。 He had told me that he would join the club sometime . 他曾经告诉我说，他会在某个时候参加俱乐部的。 I remembered that I had met him somewhere . 我记得我曾在哪儿见过他。 She thought that she would have finished what she was doing by the end of the month . 她认为在那个月底她将完成她手头上做的事。 2）if引导的宾语从句不能作介词的宾语，而只有用whether引导才行。这一点在上面刚刚讲过.（略） 3）某些动词后面，宾语从句的谓语要求用虚拟式。这一点已在"虚拟语气"一章中讨论过了，本章只作简单的复习。这类要求宾语从句的谓语用虚拟式的动词，常见的有：command（命令）, demand（要求）, desire（希望）, insist（坚持）, order（命令）, propose（提议）, recommend（推荐）, request（要求）, require（要求）, suggest（建议），等。例如： He proposed that we ( should ) set a dead line for the complement of the plan . 他提议拟定一个执行计划的期限。 C 表语从句在句子中担当表语的主谓结构称之为表语从句。它常位于句中联系动词或是起联系动词作用的动词之后.例如： The problem is where we can hold our meeting . 问题是我们可以在哪儿举行会议。 It seems that everything goes smoothly .似乎一切都进行得很顺利。 The cause is that the temperature of water is lower that needed . 其原因是水的温度低于所需要的温度。 That is what he really wants .那就是他真想要的东西。 D 同位语从句同位语从句就是在句子中担当同位语的主谓结构.在使用同位语从句时要特别注意：尽管主从连词that在同位语从句中没有任何意义，但却不能省略。另外，同位语从句常用于下面这些名词的后面（其中，斜体字的名词后面所接的同位语从句中要用虚拟语气）： fact（事实）, fear（担心、害怕）, belief（信念,意见）, evidence（证据）, hope（希望）, idea（想法） news（新闻）, doubt（怀疑）, suggestion（建议）, motion（动议）, proposal（提议）, order（命令）, recommendation（推荐），等等。例如： There is the news that an American delegation will arrive in Beijing tomorrow afternoon . 有消息说一个美国代表团将于明天下午抵达北京。 Is there any proof that the food of the plant differs from that of animals ? 是否有任何证据可以说明植物性的食物不同于动物性的食物呢？ We all know the fact that organization helps memorization. 我们都知道这样一个事实：把要记忆的材料组织起来有助于记忆。 What do you think of his proposal that we ( should ) put on a play at the English evening ? 他建议我们在英语晚会上演一个剧，你觉得怎么样？
第2个回答 2016-12-05
从句是指用于复合句中担当某个句子成分的主谓结构。虽说从句自身的句子结构是完整的， 但是它不能视为独立的句子，因为它离开了主语就无法独立、完整地表达意思。按其所能表达的意义而言,它相当于一个词或是一个词组.例如： 1) Because they talk at home while the television is on , many people think they can talk at movies as well . （状语从句）许多人在家里是边看电视边谈话，所以他们认为在电影院也可以如此。 2) Whether he comes or not doesn't make any difference to me . （主语从句） 他来与不来对我都一样。 3)There is disagreement among economists about what money is and how money is measured（宾语从句）什么是货币以及怎样计量货币经济学家之间存有分歧。 4） China is not what it used to be . （表语从句）中国不是它过去的样子了。 5） Is there any proof that the food of plant differs from that of animals ? （同位语从句）有没有什么证据说明植物性食品不同于动物性食品？ 6) Taxes consist of money that people pay to support their government . （定语从句） 税款是人们支持政府而交的钱。 如果将上面的复合句中所有的从句都独立出来，那将是这样的： 1） Because they talk at home while the television is on 2） Whether he comes or not 3） what money is and how money is measured 4） what it used to be 5） that the food of plant differs from that of animals 6） that people pay to support their government 我们很容易看出，上面的所有这些句子既不是陈述句、疑问句，也不是祁使句，更不是感叹句。也就是说，它们不是独立的句子；也只有在附属于主句后才能获得意义如下：1）因为许多人在家里是边看电视边谈话 2）他来与不来 3)什么是货币以及怎样计量货币 4)它过去的样子5)植物性食品不同于动物性食品6）人们支持政府而交的上面的这些句子在我们中文里如同是人们常说的"半截话"；在英文中也就是个"词或词组"了。 B. 我们虽然说过，从句自身的句子结构基本是完整的，但是它不同于"独立句子"的是--每个从句的最前面都好象"戴了顶帽子"即：从属关系词。由此可以看出，从句的另一个特点是：从属关系词总是立于从句之首. C. 从句的再一个特点是:一般说来（除少数倒装的情况外），从句中的语序应该是正常语序。 D. 关于从句种类的划分有两种方法：按从句的词性划分和按从句的句子功能划分。如果按从句的词性划分，从句可分为三种：名词从句、形容词从句和副词从句。如果按从句的句子功能划分（也就是按从句在句子中所担任的成分来划分），从句可分为：主语从句、宾语从句、 表语从句、同位语从句、定语从句和状语从句。其实，这两种划分从句的方法在逻辑上是一致的.我们知道，能在句子里充当主语、宾语、表语和同位语的往往是名词、代词等，所以名词从句涵盖了主语从句、宾语从句、表语从句和同位语从句。形容词和副词常分别在句中担当定语和状语，所以，形容词从句和副词从句其实分别是定语从句和状语从句。 名词从句名词从句在句中是一个相当于名词的主谓结构。我们在前面说过，名词从句含盖了主语从句、宾语从句、表语从句和同位语从句。连接这些从句与主句的关系词主要有三类： 1.从属连词：that（无有词义） , whether（是否） ,if （是否） 2.关系代词：who（谁，主格） , whom（谁，宾格）,whose谁的，所有格） , what（什么）,which（哪个，哪些） 3.关系副词：when（什么时候） where（什么地方）why（为什么） , how（怎样） 名词从句中的从属连词在从句里不担任任何成分，只起连接的作用；而关系代词和关系副词不仅仅是起连接的作用，而且还在从句里担任一定的成分;关系代词常在从句中担任主语、宾语或表语等成分；关系副词常在从句中担任状语。另外，在使用上面的这些关系词时，有几个问题值得我们注意：首先，只能用whether而不能用if的情况. 1）引导主语从句，例如： Whether we'll make a loan for the project has not been decided .（正确）我们是否要为这个项目还没有定下来。 OR: It has not been decided whether we'll make a loan for the project . （正确） If we'll make a loan for the project has not been decided .（错误） OR: It has not been decided if we'll make a loan for the project . （错误） 2）作介词的宾语，例如： I have no idea about whether I can raise the money for buying a car . （正确）我不知道我是否能为买车筹措到资金。 I have no idea about if I can raise the money for buying a car . （错误） 3）后接不定式 ，例如： He didn't know whether to go all himself first or wait for her here.(正确)他不知道是他自己先去还是在这儿等她。 He didn't know if to go all himself or wait for her here . （错误） 4）后接or not ，例如： We wonder whether they'll come in time or not.(正确) 我们担心他们会不会准时到。 We wonder if they'll come in time or not . （错误）其次，what引导的名词从句表达的意思是"……所……的"。这个"所怎么的"定义根据"从句谓语的动作意义"而定。例如： I don't understand what you said.我不理解你所说的话。 What he needs is to practice more.他所需要的是勤于练习。 Money is what she is really after.金钱是她所真正追求的东西。 People have different ideas about what happiness means . 人们对于幸福的含义有不同见解。最后，要了解 -ever = no matter ，用于表示强调，意为"无论……"。也就是说： whatever = no matter what（无论什么） whoever = no matter who（无论谁） whichever = no matter which（无论那个） whenever =no matter when （无论何时） wherever = no matter where（无论何地） however = no matter how （无论怎样） A 主语从句用作主语的主谓结构称之为主语从句。例如： Whether he'll come or not remains a question . 他是否会来依然是一个问题。 Whoever says that is not allowed .无论谁这样说都是不允许的。 That she reads English aloud every morning helps her a lot in the improvement of her English study . 她每天早晨朗读英文对提高她的英语学习起了很大的作用。 要点提示在使用主语从句中，有几个问题值得我们注意： 1）尽管主从连词that在主语从句中没有任何意义,但一般不能省略。 That there is no elevator in the building is the critical inconvenience .这幢楼里没有电梯是极大的不便之处。 It is necessary (that) he have his further study incollege.(当主语从句在后面时，连词that可以省去)他在大学进一步深造是完全必要的。 2）为了保持句子平衡或在正式文体中,常用先行It代替主语从句而将主语从句置于句末。 It remains a question Whether he'll come or not . 他是否会来，依然是一个问题。 It is not allowed Whoever says that. 无论谁这样说都是不允许的。 3）在It + be +形容词/ 名词 + that从句的结构中，由于某些形容词/ 名词的原因，that从句中的谓语动词要用虚拟式。这类形容词/ 名词常见的有： essential（绝对必要的）, important（重要的）, advisable（明智的）, desirable（希望能够的）, imperative（必须的）, natural（自然的）, necessary必要的）, regretful（遗憾的）, strange（奇怪的）, proper（适当的）, urgent（紧急的）, duty（义务、责任）, a pity （遗憾）, no wonder（难怪）, a regret（遗憾）。例如： It is strange that he ( should ) say so . 他居然会这样说，真是奇怪。 It is a great pity that you ( should ) think so . 他居然会这样想，真是一件憾事。 It is natural that a bird ( should ) rest in trees . 鸟在树上安歇是很自然的。 It is a wonder that he should have passed the exam. 他这次考试居然会及格，真是个奇迹。 4）以what引导的主语从句常用于句首表示强调。 What they need now is financial aid . 他们现在所需要的是经济援助。 What she thinks of me doesn't mean much to me . 她怎么样看我，对我来说无所谓。 What you have said hurt her a lot .你所说的话对她伤害很大。 B 宾语从句用作谓语动词、介词以及非谓语动词形式的宾语的主谓结构称之为宾语从句。也就是说,只要是用一个主谓结构去充当宾语，那么这个主谓结构就称为宾语从句。 例如： I believe that he will find a job in that publisher .（作谓语动词的宾语）我相信，他一定会在那家出版社找到工作。 He laughed at what they said . （作介词的宾语）她对他们说的话，一笑置之。 要点提示在使用宾语从句中，有几个问题值得我们注意： 1）宾语从句与主句的时态一致性问题这种一致性的要求,只有当主句的谓语动词用于"过去时区"的时候才存在。凡是在"过去时区"内的各种不同时态都在其中。另外，这种一致性只要求宾语从句的谓语动词也用于"过去时区"即可，至于用什么样具体的时态就要依从句的需要而定了。 He had told me that he would join the club sometime . 他曾经告诉我说，他会在某个时候参加俱乐部的。 I remembered that I had met him somewhere . 我记得我曾在哪儿见过他。 She thought that she would have finished what she was doing by the end of the month . 她认为在那个月底她将完成她手头上做的事。 2）if引导的宾语从句不能作介词的宾语，而只有用whether引导才行。这一点在上面刚刚讲过.（略） 3）某些动词后面，宾语从句的谓语要求用虚拟式。这一点已在"虚拟语气"一章中讨论过了，本章只作简单的复习。这类要求宾语从句的谓语用虚拟式的动词，常见的有：command（命令）, demand（要求）, desire（希望）, insist（坚持）, order（命令）, propose（提议）, recommend（推荐）, request（要求）, require（要求）, suggest（建议），等。例如： He proposed that we ( should ) set a dead line for the complement of the plan . 他提议拟定一个执行计划的期限。 C 表语从句在句子中担当表语的主谓结构称之为表语从句。它常位于句中联系动词或是起联系动词作用的动词之后.例如： The problem is where we can hold our meeting . 问题是我们可以在哪儿举行会议。 It seems that everything goes smoothly .似乎一切都进行得很顺利。 The cause is that the temperature of water is lower that needed . 其原因是水的温度低于所需要的温度。 That is what he really wants .那就是他真想要的东西。 D 同位语从句同位语从句就是在句子中担当同位语的主谓结构.在使用同位语从句时要特别注意：尽管主从连词that在同位语从句中没有任何意义，但却不能省略。另外，同位语从句常用于下面这些名词的后面（其中，斜体字的名词后面所接的同位语从句中要用虚拟语气）： fact（事实）, fear（担心、害怕）, belief（信念,意见）, evidence（证据）, hope（希望）, idea（想法） news（新闻）, doubt（怀疑）, suggestion（建议）, motion（动议）, proposal（提议）, order（命令）, recommendation（推荐），等等。例如： There is the news that an American delegation will arrive in Beijing tomorrow afternoon . 有消息说一个美国代表团将于明天下午抵达北京。 Is there any proof that the food of the plant differs from that of animals ? 是否有任何证据可以说明植物性的食物不同于动物性的食物呢？ We all know the fact that organization helps memorization. 我们都知道这样一个事实：把要记忆的材料组织起来有助于记忆。 What do you think of his proposal that we ( should ) put on a play at the English evening ? 他建议我们在英语晚会上演一个剧，你觉得怎么样？
第3个回答 推荐于2017-12-16
第4个回答 2017-03-10
1.主语从句
1）主语从句可直接位于主语的位置，如果从句较长，谓语又较短，可用it作形式主语，而将从句放在句末。常见的句型有：
*It is a fact\a pity\a question\good news that...
*It seems\appears\happened\has turned out that...
*It is clear\important\likely\possible that...
*It is said\reported\estimated\has been proved that...
It is said that comic books create a connection between people of the same generation.
It seems that the performance is very useful.
2)what引导的主语从句表示“...的东西时”，一般不用it作形式主语。
What we lack is experience.
3)what,who,when,why,whether等词含有各自的疑问意义，但它们引导的主语从句，都用陈述语序。
How the plan is to be carried out should be discussed again.
I did know why I felt like crying.
2.宾语从句
1）宾语从句可位于及物动词、介词和某些形容词后。连词that常可省略。介词后一般接疑问词引导的宾语从句。in that(因为),except that(除了),but that(只是）已构成固定搭配，其他介词后一般不接that引导的宾语从句。
*I promised that I would change the situation.
*All this is different from what American young people would say about friendship.
*He is certain that watching so much television is not good for children.
*This article is well-written except that it is a bit too long.
2)宾语从句后如有宾补，要用形式宾语it来代替，而把宾语从句移至宾补之后。
He has made it clear that he would not change his mind.
3)在think,believe,suppose,expect等动词后的宾语从句中，如果谓语是否定的，一般将否定词移至主句谓语上，宾语从句则变成肯定形式。
He didn't think that the money was well spent.
3.表语从句
表语从句出现在结构为“主语+系动词+表语从句”的句子中。表语从句除可用that,what,when,why,whether,how等引导外，还可由because,as if(though)等引导。that常可省略。如主句主语为reason,只能用that引导表语从句，不可用because.
Perhaps the most important thing to remember is that there is no one common type of life in America.
The reason why so many people died there is that there were not enough food supplies.
It looks as if successful international cultural communication will make the world smaller.
4.同位语从句
同位语从句用于对前面出现的名词作进一步说明，一般用连词that引导，由于先行名词的意义不同，也可用whether,who,when,where,what,why,how等引导。常见的先行名词有fact,idea,belief,news,hope,conclusion,evidence,suggestion,order,problem,report,decision.有时由于谓语较短，将同位语从句位于谓语之后。
She finally made the decision that she would join the fashion show.
I had no idea how many books I could borrow at a time.
The news came that their team had won the championship.
5.定语从句
定语从句所修饰的先行词可以是名词或代词，也可以是一个句子。定语从句通常位于先行词之后，由关系代词或关系副词引导。
*限制性定语从句
限制性定语从句修饰先行词，对先行词起修饰作用，紧接先行词之后，无逗号，若省去，原句意思不完整。引导定语从句的关系代词有who,whom,whose,which,that等。who,whom,whose用于指人，whose有时也可指物，相当于of which；which用于指物；that既可指人也可指物，但只用于限制性定语从句中。关系代词除了引导定语从句，替代先行词外，还在从句中担任主语、宾语、定语等。
The computers and cables which make up the Internet are owned by people and organizations.
Those who live alone or who are sick may have trouble in getting close to other people.
The girl whose parents died in an accident is living with her grandmother.
1)当先行词是all,anything,everything,something,nothing等不定代词或先行词前有first,last,any,few,much,some,no,only以及形容词最高级修饰时，只能用关系代词that引导从句。
That is all that I've heard from him.
He's the first person that I'm going to interview this afternoon.
2)关系代词的省略
在从句中作宾语的关系代词常可省略。关系代词紧跟介词，作介词宾语时不可用that，只可用which或whom引导从句，并且不可省略，但当介词位于宾语从句句末时，作为介词宾语的关系代词仍可用that，也可省略。
This is one of those things with which we have to put up.
This is one of those things (which\that) we have to put up with.
3)引导定语从句的关系副词有when,where,why等。关系副词在从句中作状语，意义上相当于一个“介词+which”的结构。
Even in comic books where(=in which) there are no words,the stories are fully expressed through the drawings.
No one knows the reason why(=for which) he was so angry that day.
*非限制性定语从句
非限制性定语从句既可修饰先行词，也可修饰整个主句，起补充说明作用，与主句之间有逗号隔开，若省去，原句意思不受影响。不可用that引导非限制性定语从句。关系词不可省略。
Every object has a gravitational pull,which is rather like magnetism.
*“介词+which\whom\whose”引导的定语从句
“介词+which\whom\whose”可引导限制性定语从句，也可引导非限制性定语从句，该结构中介词的选择取决于从句谓语动词的固定搭配，或先行词的习惯搭配。
This is the computer on which he spent all his savings
It is written by a person with whom we are all familiar.
*as引导的定语从句
as引导的定语从句主要用于“such...as”及“the same...as”的结构中，代替先行词是人或物的名词。as引导非限制性定语从句时，代替整个主句，从句可位于主句之前、之后或中间。
These are not such problems as can be easily solved.(as代替先行词problems)
As is mentioned above,no single company or group can control what happens on the Internet.(as代替主语)
6.状语从句
*时间状语从句
引导时间状语从句的从属连词和词组有：
1）when,whenever,while,as,after,before,since,till,until,once等。
We have learnt quite a lot about it since we came here.
2)as soon as,hardly(scarcely)...when,no sooner...than,each(every) time,the moment,immediately(that)等。
As soon as I sent an e-mail message,I received positive responses.
The moment he heard the good news,he jumped with joy.
*地点状语从句
引导地点状语从句的连词是where,wherever.
Wherever she went,she took her little daughter with her.
*原因、结果和目的状语从句
1）引导原因状语从句的从属连词有：because,as,since,now(that),seeing that,considering that,in that等。
Considering that he is a freshman,we must say he is doing well.
2)引导结果状语从句的连词有：so...that,such...that,so that,that,so等。
Mickey Mouse is so attractive that the children are reluctant to leave.
3)引导目的状语从句的连词有：so that,in order that,for fear that,lest等，从句常使用may,might,can,could,would等情态动词。
We got up early this morning so that we could catch the first bus to the railway station.
*条件和让步状语从句
1）引导条件状语从句的连词和词组有if,unless,as(so) long as,on condition that,in case,provided(providing) that,supposing等。
As long as you have the right equipment,you can use a telephone line to transmit computer data.
2)引导让步状语从句的连词和词组有though,although,whether,even though,even if,no matter what(when,how...),whatever(whenever,wherever,however....)等。though,even if等引导状语从句可转换成含有as的部分倒装结构，具有强调意义。其结构为“形容词（副词、动词、名词）+as+主语+谓语”。
No matter what you may say,I would not change my mind.
Young as he is,he is quite experienced in this work.(=though he is young)
Child as he is,he can speak English fluently.(=though he is a child)
*方式状语从句
引导方式状语从句的连词有as,just as,as if,as though等。as if,as though引导的状语从句中，谓语动词常用虚拟语气，表示与事实相反。
The young man made the experiment just as the teacher had taught him.
Everything went on as usual as if nothing had happened.
1）主语从句可直接位于主语的位置，如果从句较长，谓语又较短，可用it作形式主语，而将从句放在句末。常见的句型有：
*It is a fact\a pity\a question\good news that...
*It seems\appears\happened\has turned out that...
*It is clear\important\likely\possible that...
*It is said\reported\estimated\has been proved that...
It is said that comic books create a connection between people of the same generation.
It seems that the performance is very useful.
2)what引导的主语从句表示“...的东西时”，一般不用it作形式主语。
What we lack is experience.
3)what,who,when,why,whether等词含有各自的疑问意义，但它们引导的主语从句，都用陈述语序。
How the plan is to be carried out should be discussed again.
I did know why I felt like crying.
2.宾语从句
1）宾语从句可位于及物动词、介词和某些形容词后。连词that常可省略。介词后一般接疑问词引导的宾语从句。in that(因为),except that(除了),but that(只是）已构成固定搭配，其他介词后一般不接that引导的宾语从句。
*I promised that I would change the situation.
*All this is different from what American young people would say about friendship.
*He is certain that watching so much television is not good for children.
*This article is well-written except that it is a bit too long.
2)宾语从句后如有宾补，要用形式宾语it来代替，而把宾语从句移至宾补之后。
He has made it clear that he would not change his mind.
3)在think,believe,suppose,expect等动词后的宾语从句中，如果谓语是否定的，一般将否定词移至主句谓语上，宾语从句则变成肯定形式。
He didn't think that the money was well spent.
3.表语从句
表语从句出现在结构为“主语+系动词+表语从句”的句子中。表语从句除可用that,what,when,why,whether,how等引导外，还可由because,as if(though)等引导。that常可省略。如主句主语为reason,只能用that引导表语从句，不可用because.
Perhaps the most important thing to remember is that there is no one common type of life in America.
The reason why so many people died there is that there were not enough food supplies.
It looks as if successful international cultural communication will make the world smaller.
4.同位语从句
同位语从句用于对前面出现的名词作进一步说明，一般用连词that引导，由于先行名词的意义不同，也可用whether,who,when,where,what,why,how等引导。常见的先行名词有fact,idea,belief,news,hope,conclusion,evidence,suggestion,order,problem,report,decision.有时由于谓语较短，将同位语从句位于谓语之后。
She finally made the decision that she would join the fashion show.
I had no idea how many books I could borrow at a time.
The news came that their team had won the championship.
5.定语从句
定语从句所修饰的先行词可以是名词或代词，也可以是一个句子。定语从句通常位于先行词之后，由关系代词或关系副词引导。
*限制性定语从句
限制性定语从句修饰先行词，对先行词起修饰作用，紧接先行词之后，无逗号，若省去，原句意思不完整。引导定语从句的关系代词有who,whom,whose,which,that等。who,whom,whose用于指人，whose有时也可指物，相当于of which；which用于指物；that既可指人也可指物，但只用于限制性定语从句中。关系代词除了引导定语从句，替代先行词外，还在从句中担任主语、宾语、定语等。
The computers and cables which make up the Internet are owned by people and organizations.
Those who live alone or who are sick may have trouble in getting close to other people.
The girl whose parents died in an accident is living with her grandmother.
1)当先行词是all,anything,everything,something,nothing等不定代词或先行词前有first,last,any,few,much,some,no,only以及形容词最高级修饰时，只能用关系代词that引导从句。
That is all that I've heard from him.
He's the first person that I'm going to interview this afternoon.
2)关系代词的省略
在从句中作宾语的关系代词常可省略。关系代词紧跟介词，作介词宾语时不可用that，只可用which或whom引导从句，并且不可省略，但当介词位于宾语从句句末时，作为介词宾语的关系代词仍可用that，也可省略。
This is one of those things with which we have to put up.
This is one of those things (which\that) we have to put up with.
3)引导定语从句的关系副词有when,where,why等。关系副词在从句中作状语，意义上相当于一个“介词+which”的结构。
Even in comic books where(=in which) there are no words,the stories are fully expressed through the drawings.
No one knows the reason why(=for which) he was so angry that day.
*非限制性定语从句
非限制性定语从句既可修饰先行词，也可修饰整个主句，起补充说明作用，与主句之间有逗号隔开，若省去，原句意思不受影响。不可用that引导非限制性定语从句。关系词不可省略。
Every object has a gravitational pull,which is rather like magnetism.
*“介词+which\whom\whose”引导的定语从句
“介词+which\whom\whose”可引导限制性定语从句，也可引导非限制性定语从句，该结构中介词的选择取决于从句谓语动词的固定搭配，或先行词的习惯搭配。
This is the computer on which he spent all his savings
It is written by a person with whom we are all familiar.
*as引导的定语从句
as引导的定语从句主要用于“such...as”及“the same...as”的结构中，代替先行词是人或物的名词。as引导非限制性定语从句时，代替整个主句，从句可位于主句之前、之后或中间。
These are not such problems as can be easily solved.(as代替先行词problems)
As is mentioned above,no single company or group can control what happens on the Internet.(as代替主语)
6.状语从句
*时间状语从句
引导时间状语从句的从属连词和词组有：
1）when,whenever,while,as,after,before,since,till,until,once等。
We have learnt quite a lot about it since we came here.
2)as soon as,hardly(scarcely)...when,no sooner...than,each(every) time,the moment,immediately(that)等。
As soon as I sent an e-mail message,I received positive responses.
The moment he heard the good news,he jumped with joy.
*地点状语从句
引导地点状语从句的连词是where,wherever.
Wherever she went,she took her little daughter with her.
*原因、结果和目的状语从句
1）引导原因状语从句的从属连词有：because,as,since,now(that),seeing that,considering that,in that等。
Considering that he is a freshman,we must say he is doing well.
2)引导结果状语从句的连词有：so...that,such...that,so that,that,so等。
Mickey Mouse is so attractive that the children are reluctant to leave.
3)引导目的状语从句的连词有：so that,in order that,for fear that,lest等，从句常使用may,might,can,could,would等情态动词。
We got up early this morning so that we could catch the first bus to the railway station.
*条件和让步状语从句
1）引导条件状语从句的连词和词组有if,unless,as(so) long as,on condition that,in case,provided(providing) that,supposing等。
As long as you have the right equipment,you can use a telephone line to transmit computer data.
2)引导让步状语从句的连词和词组有though,although,whether,even though,even if,no matter what(when,how...),whatever(whenever,wherever,however....)等。though,even if等引导状语从句可转换成含有as的部分倒装结构，具有强调意义。其结构为“形容词（副词、动词、名词）+as+主语+谓语”。
No matter what you may say,I would not change my mind.
Young as he is,he is quite experienced in this work.(=though he is young)
Child as he is,he can speak English fluently.(=though he is a child)
*方式状语从句
引导方式状语从句的连词有as,just as,as if,as though等。as if,as though引导的状语从句中，谓语动词常用虚拟语气，表示与事实相反。
The young man made the experiment just as the teacher had taught him.
Everything went on as usual as if nothing had happened.
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