第二章 · 复合句（一）
第二章-复合句（一）
英语句子按照其结构分为简单句、并列句和复合句。
简单句：只有一个完整的主、谓结构的句子。
The woman arrived at the house.
The woman arrived at the house and knocked at the door.
The woman and the man arrived at the house and knocked at the door.
大家在判断简单句与否时，一定要参照定义，而不能简单看句子的长短。
并列句：两个或两个以上的简单句用并列连词或标点符号连接而成的句子叫并列句。常见的并列词有and,but,so, yet等。（参见连词部分知识）
We fished all day ,but we didn't catch a thing.（错误）
如果非要用标点符号连接可以改为，
We fished all day；we didn‘t catch a thing.（不能用逗号，只能用分号连接。）
I found a bucket, put it in the sink ,and turned the tap on. 我找到一个水桶，把它放在水槽里，然后打开了水龙头。
复合句
复合句又称主从复合句，由一个主句和一个或多个从句构成。复合句可以分为三大类，即：名词性从句、定语从句（形容词性从句）和状语从句。
复合句：
名词性从句——主语从句、宾语从句、表语从句、同位语从句。
定语从句。
状语从句。
一、名词性从句
在复合句中，充当句子主语的从句叫做主语从句。
由连词that, whether,if引导的主从，在从句中不充当任何成分，但是不能省略。
That the earth travels around the sun is a truth.
Whether she will come or not depends on the weather.
由连接代词who,which等及关系副词when,why ,where 等引导 主语从句，在从句中关系代词充当主语，宾语或者是状语，不能省略。
What you need is a good rest.（what在从句中作need的宾语）
Whichever（of you） comes in first will receive a prize（主语）
是指整个宾语从句都作前面的及物动词、介词和少数形容词的宾语，就像宾语本身一样。
I know that you are right.（作及物动词的宾语）
I was surprised at what he said to his ex-lover.（作介词后的宾语）
I am sure that he will come.（作形容词后的宾语）
由连词that引导的宾从，在从句中不充当任何成分，没有意义，一般情况下可以省略。但是如果从句是并列句时，第二个分句前的that不可以省略。
We know（that） we can make our best to finish the tasks and that（不能省略）we must do so.
由who,what,whom,wh-ever等连接词引导的宾语从句，从句要用陈述语序。
I want to know what you have talked about.（what在宾从中作about的宾语）
I cannot tell which one is true.（which在宾从中作主语）
表语从句和表语一样位于系动词之后
The fact is that he doesn't like you.
That is just what I want to say.
同位语从句通常是由that来引导， 并且不可以省略，一般是紧跟着名词之后。
The news that we have won the game makes us happy.
We cannot accept the fact that we lose the game.
注意，同位语从句有时不是紧跟名词，而是被其他的词隔开了，一定要看仔细，尤其是在做完形填空题时。
The rumor spread that a new hospital will be built here.
The story goes that they are divorced.
补充名词性从句重要知识点：
it作形式主语的几种情况
it+be +形容词+that从句
It is necessary/ important/ obvious that……
it+be+ed-分词+that从句
It is believed /known to all /has been decided that……
it+be+名词+that从句
It is common knowledge /a surprise / a fact that ……
It +不及物动词+that分句
It appears /happened /occurred to me that ……
二、定语从句
在复合句中，修饰某一名词或代词的从句叫做定语从句。
The man who lives next to us is a policeman.
You must do everything that I do.
上面两句中的man和everything是定语从句所修饰的词，叫先行词，定语从句放在先行词的后面，引导定语从句的词有：
关系代词：that, which, who, whom, whose.
关系副词：where, when, why.
选用原则是看它指人还是指物，以及在从句中担任什么句子成分。
The boys who/that are playing football are from Class 1.
（关系代词指代先行词人boys，在从句中作主语，所以who和that都可以。）
Mr. Liu is the person（whom/that） you talked about.（关系代词指代先行词人person,在从句中作宾语。）
