九年级英语语法----复合句复合句由一个主句和一个或一个以上的从句构成。

主句是全句的主体，通常可以独立存在；从句则是一个句子成分，不能独立存在。

从句不能单独成句，但它也有主语部分和谓语部分，就像一个句子一样。

所不同在于，从句须由一个关联词引导。

复合句：句子中有一个或一个以上的从句，叫做复合句。

复合句可分为：1).定语从句；2).状语从句；3).名词性从句(宾语从句，表语从句，同位语从句)一、定语从句定语从句在句子中作定语，用来修饰一个名词、名词词组或者代词。

1. 被修饰的名词、名词词组或代词叫做先行词；2. 在先行词和定语从句之间起连接作用的词叫做引导词。

3. 引导词分为“关系代词”和“关系副词”。

关系代词有：who, whom, whose, that, which。

（没有what）关系副词有：when, where, why。

注意：关系副词里面没有how。

1.·关系代词：who(在从句中主要作主语，在非正式语体里who还可以作从句中的宾语。

He is the man who wants to see you.He is the man who I saw in the park yesterday.·关系代词：whom（whom在从句中作动词或介词的宾语）He is the man （whom）I saw in the park yesterday.·关系代词：whose （只能用作定语, 若指物，它还可以同of which互换）。

They rushed over to help the man whose car had broken down.Please pass me the book whose cover is green. （of which the cover/the cover of which）·关系代词：which（1）which指物，在从句中作主语或宾语，作宾语时在非正式语体中可以省略。

They needed a plant which didn't need as much water as rice.The farm (which) we visited yesterday is located in the suburb of Beijing.·关系代词：which（2）当在which和that面前进行选择的情况下，一般情况下要选which：1.在非限制性定语从句中通常用which作引导词，而不能用that做非限制性定语从句的引导词。

定语从句有限制性和非限制性两种。

限制性定语从句是先行词不可缺少的部分，去掉它主句意思往往不明确；非限制性定语从句是先行词的附加说明，去掉了也不会影响主句的意思，它与主句之间通常用逗号分开，2. 修饰整个主句。

I never met Julia again after that, which was a pity.3. 修饰谓语部分。

He can swim in the river, which I cannot.4. 介词+ whichThey are all questions to which there are no answers.·关系代词：that（1）that多用来指物，有时也可以用来指人；在从句中作主语或宾语。

指物的时候多用that，也可用which。

It’s a question that (which) needs careful consideration. （指物，作主语。

）Who is the man that is reading a magazine under the tree? （指人，作主语。

）The girl (that) we saw yesterday is Tom’s sister. （指人，作宾语，可省略。

）·关系代词：that（2）在以下的情况中，只能用that作引导词，而不能用which作引导词。

1. 先行词为all , everything, anything, nothing, little等不定代词时。

All (that) she lacked was training.2. 先行词被形容词最高级、序数词修饰时This is the best film that I have ever seen.3. 先行词被序数词和the last, the only, the very, the same修饰时4. 先行词被all, every, no, some, any, little, much等修饰时。

5. 先行词中既有人又有物时They talked about the teachers and the schools that they had visited.6. 主句是含有who或which的特殊疑问句，为了避免重复时关系副词when (在定语从句中作时间状语，可用介词+which替换)Do you remember the first day when/on which we studied in the school library?关系副词where （在定语从句中作地点状语，可用介词+which替换）Is this the village where/in which your father was born?关系副词why（在定语从句中作原因状语，可用for+which替换）I could hardly tell him the reason why/ for which I was so sad.二、状语从句1 地点状语从句,由where, wherever 引导。

Where I live there are plenty of trees.Wherever I am I will be thinking of you.2 方式状语从句由as, (just) as…so…, as if, as though引导1）as, (just) as…so…引导的方式状语从句通常位于主句后，但在(just) as…so…结构中位于句首，这时as从句带有比喻的含义，意思是"正如…"，"就像"，多用于正式文体，例如：Always do to the others as you would be done by.你希望人家怎样待你，你就要怎样待人。

As water is to fish, so air is to man.我们离不开空气，犹如鱼儿离不开水。

Just as we sweep our rooms, so we should sweep backward ideas from our minds.正如打扫房屋一样，我们也要扫除我们头脑中落后的东西。

2）as if, as though两者的意义和用法相同，引出的状语从句谓语多用虚拟语气，表示与事实相反，有时也用陈述语气，表示所说情况是事实或实现的可能性较大。

汉译常作"仿佛……似的"，"好像……似的"，例如：He looks as if (as though) he had been hit by lighting.他那样子就像被雷击了似的。

（与事实相反，谓语用虚拟语气。

）It looks as if the weather may pick up very soon.看来天气很快就会好起来。

（实现的可能性较大，谓语用陈述语气。

）说明：as if / as though也可以引导一个分词短语、不定式短语或无动词短语，例如：He stared at me as if seeing me for first time.他目不转睛地看着我，就像第一次看见我似的。

He cleared his throat as if to say something.他清了清嗓子，像要说什么似的。

3 原因状语从句because, since, as和for等词引导1）because语势最强，用来说明人所不知的原因，回答why提出的问题。

当原因是显而易见的或已为人们所知，就用as或since。

I didn't go, because I was afraid.Since /As the weather is so bad, we have to delay our journey.2）由because引导的从句如果放在句末，且前面有逗号，则可以用for来代替。

但如果不是说明直接原因，而是多种情况加以推断，就只能用for。

He is absent today, because / for he is ill.He must be ill, for he is absent today.4 目的状语从句that, so that, in order that, in case等词引导You must speak louder so that /in order that you can be heard by all.Better take more clothes in case the weather is cold.5 结果状语从句so… that 或such…that引导such 是形容词，修饰名词或名词词组，so 是副词，只能修饰形容词或副词。

so 还可与表示数量的形容词many, few, much, little连用，形成固定搭配。

so foolish such a foolso nice a flower such a nice flowerso many / few flowers such nice flowersso much / little money. such rapid progressso many people such a lot of people（so many 已成固定搭配，a lot of 虽相当于many，但 a lot of 为名词性的，只能用such 搭配。

）so…that与such…that之间的转换既为so与such之间的转换。

The boy is so young that he can't go to school.He is such a young boy that he can't go to school6 条件状语从句if, unless, as/so long as, on condition thatif 引导的条件句有真实条件句和非真实条件句两种。