概念：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，
主句为句子的主体，从句不能独立，只能做句子的一个成分。 从句担任什么句子成分，这个从句就叫该成分的从句。 根据从句在句中的作用，可分为名词性从句、定语从句和状语从句。 一、名词性从句
名词性从句相当于名词，可作主句的主语、表语、宾语和同位语。因此，名词性从句可分为主语从句、表语从句、宾语从句、同位语从句四种。 (从属连词：用来连接主句和从句的连词称为从属连词) 从 属 连接词：that/whether/if 不充当从句的任何成分 连 词 连接代词：who/whom/whose、what、which当主/宾/表/定语 (标签) 连接副词：when/where/how/why 充当从句的状语 ⚫ 主语从句 1. 由连接词引导
eg: That the earth turns around the sun is known to all. Whether he will come or not is not yet known. 2. 由连接代词引导
eg: Who will go is not important. What we need is more practice. 3. 由连接副词引导
eg: Where the meeting will be held hasn’t been decided. When he will return is an important question.
4. 另外也可以用it作形式主语，主语从句作真正主语放句子后面 eg: It’s a pity that she has made such a foolish mistake.
It’s reported that three people were killed in the traffic
accident.
It doesn’t matter whether he will come or not. ⚫ 表语从句 1. 由连接词引导
eg: The question is whether we should ask them for help. 2. 由连接代词引导
eg: China is not what it used to be. 3. 由连接副词引导
eg: That is why he didn’t pass the exam.
4. 表语从句还可以由as if /as though/ as/because来引导 eg: It looks as if it were going to rain. Things are not always as they seem to be. It’s because you eat too much. ⚫ 宾语从句
宾语从句在复合句中作及物动词、介词、形容词的宾语。 I think that watching TV too much is bad for people’s health. I wonder=want to know if you can do me a favour. I wonder why he refused my invitation.
He asked me whose handwriting is the best in the class. I don’t know which school he is in.
The teacher is pleased with what he has said. I always think of how I can improve my English. I’m afraid that I can’t accept your invitation.
We are glad that our football team has won the match. 另外也可以用it作形式宾语，宾语从句作真正宾语放句子后面 eg: I find it necessary that we should ask him for advice.
⚫ 同位语从句
同位语从句一般放在某些抽象名词如：fact/ news/ idea/ thought/ advice/ suggestion/ truth/ hope/ problem/ question/ information/ order/ belief/ doubt/ fear等的后面，说明该名词的具体内容。
eg: The news that he has been elected president of the United States is
true. I have no idea when he will be back. ⚫ 名词性从句需注意的几个问题 1. 名词性从句用陈述语气 eg: I don’t know where he has gone.
2. 名词性从句中的宾语从句其引导词that可以省略
eg: I think (that) watching TV too much is bad for people’s health.
3. 名词性从句中的宾语从句为介宾时，不用which引导， 而用what 引导。 eg: Are you sorry for what you have done? 4. 用whether而不用if表“是否”的情况 ① 用来引导主语从句放句首
eg: Whether we shall attend the meeting hasn’t decided yet. ② 用来引导表语从句和同位从句
eg: The question is whether the film is worth seeing.
eg: The news whether our team has won the match is unknown. ③ 作介词宾语，介词有时可以省略
eg: It all depends (on) whether they will support us.
④ 后面直接跟不定式时
eg: He doesn’t know whether to stay or not.
⑤ 后面跟or not
eg: We didn’t know whether she was ready or not. 二、 定语从句
定语从句起定语作用，修饰句中的名词或代词，被修饰的名词或代词称为先行词。
从属 关系代词：who/whom/whose/which/that/as当主/宾/定语
连词 关系副词：wh en/where/why 充当从句的状语 1、 先行词为人时，从属连词在句中作主语：who/that
作宾语：whom/that/who(可省略)
eg: This is the man who/that helped me.
The doctor (whom/that) you are looking for is in the room. 2、 先行词为物时，从属连词在句中作主语：which/that
作宾语：which/that(可省略)
eg: The building which/that stands near the river is our school. This is the book (which/that) you need. 3、 先行词为时间时，从属连词在句中作状语：when
作宾语：which/that(可省略)
eg: I will never forget the day when I met Mr. Liu.
I will never forget the day (which/that) we spent together. 4、 先行词为地点时，从属连词在句中作状语：where
作宾语：which/that(可省略)
eg: This is the factory where my father once worked. This is the factory (which/that) we visited last week. 5、 先行词为原因时，从属连词在句中作状语：why
作宾语：which/that(可省略)
eg: I don’t know the reason why you were absent from the
meeting, but I’m sure that someone will tell me the reason (which/that) you haven’t told me. 6、 从属连词whose，其先行词既可为人也可为物，在从句中作定语
eg: This is the scientist whose name is known all over the country. Nobody wants the house whose roof has fallen in. 7、 关系代词选用that而不用which或who的情况 ① 先行词既有人又有物
eg: They talked of things and persons that they remembered in the
school.
② 当主句以which或who开头时，定语从句用that引导以避免重复 eg: Which is the bike that you lost? Who is the boy that was here just now.
③ 先行词是不定代词all/few/little/much/something/anything/nothing
等 eg: All that we have to do is to practise more. ④ 先行词被all/ any some/few/little/every/no等修饰时
eg: I have read all the books that you gave me.
⑤ 先行词被the only/the very/the same/the last/just等修饰时 eg: He is the only person that I want to talk to. ⑥ 先行词是系数词或形容词最高级或者被它们修饰时 eg: The train is the last that will go to Suzhou. This is the best film that I have ever seen.
⑦ 当先行词在主句中作表语，而关系代词也在从句中作表语时 eg: Shanghai is no longer the city that it used to be.
8、限制性定语从句与非限制性定语从句是有含义区别的
eg: She has two sons who are PLA man. 限制性定语从句
她有两个当解放军的儿子。(她可能还有其它的儿子但不当解放军) She has two sons, who are PLA man. 非限制性定语从句 她有两个儿子，他们都是解放军。(她有且只有两个儿子)
① 非限制性定语从句与主句之间一般用逗号隔开，而限制性定语
从句与主句之间不用逗号隔开。 ② 非限制性定语从句不用that引导，一般用which或as来引导。 ③ 非限制性定语从句的引导词which有时指代前面的整个句子。 eg: He gave his mother a colour TV set for her birthday, which
pleased her a lot. 9、由that引导的定语从句与由that引导的同位语从句 eg: The train that has just left is for Beijing.
The truth that the earth moves around the sun is known to all. ① 先行词是具体的名词或代词还是抽象名词
② 作用：是修饰限定(……的)还是补充说明(具体内容)
③ that在从句中是否充当成分：定语从句中有，同位语从句中无 ④ that是否可以省略：定语从句中作宾语可以省略，同位语从句中不能省略。 10、as与which的区别
① 引导非限制性定语从句，which只放句中，as可放句首或句中 ② as常与前面the same、such等呼应使用
eg: Such people as you discribe are thought to be fools nowadays. He is not the same man as he was. 他和过去不同了。 ③ as有“正如”、“就像”的意思而which没有 eg: as it is said above as it is
11、分隔定语从句：一般来讲定语从句要紧跟在先行词的后面，但有
时中间由一个定语、状语或谓语隔开称为分隔定语从句。 eg: There is an expression in his eyes that I can’t understand. The days are gone forever when Chinese people were looked
down upon. 12、定语从句中关系代词、关系副词在从句中充当一个成分，因此，
使用时要注意避免句子成分的重复出现。 eg: Let me have a look at the dictionary that you bought it yesterday. This is the house where I lived in two years ago. 句中的where = in which (关系副词 = 关系代词 + 介词) 三、 状语从句
状语从句在复合句中作状语，可分为时间、地点、条件、原因、结果、目的、方式、让步、比较状语从句共九种。 ⚫ 时间状语从句
时间状语从句常用when/while/as/after/before/since/until/as soon as等来引导，主句用将来时，从句用一般现在时表将来。 eg: I will go on with the work when I come back tomorrow. We will wait until the doctor comes. ① when/ while/ as表示“当……的时候” eg: I will tell her about that when I see her. As he walked along the street, he sang happily.
② as soon as/ the moment/ immediately/ directly/ instantly表示 “一……就”
eg: I will tell you as soon as I know.
③ hardly…when…/ no sooner…than…表示“刚……就” 主句用had done, 从句用did, 主句用倒装
eg: Hardly had I entered the room when I heard a loud noise. ⚫ 地点状语从句：注意与定语从句区分
I shall go where working conditions are difficult. 地点状语从句 I shall go to the place where working conditions are difficult.定语从句 ⚫ 原因状语从句
原因状语从句常用because/since/now (that)/as/for等来引导 eg: Since the two children were brought up in the south, they have never seen snow. Now that you are well again, you can go on with your work. As it is getting very late, we have to go home.
As he didn’t know much English, he often took a dictionary with him. We must start early, for we have a long way to go. 以下几种情况只能用becarse ① 回答why提出的问题； ② 用来引导表语从句；
eg: He didn’t speak to you, it was because he didn’t recognize you. ③ 用在强调原因状语从句的强调句中；
④ 当从属连词前有only/just/simply等修饰时：
eg: You shouldn’t get angry just because some people speak ill of you.
because + 句子 注意 because of + 名词或短语 区别
⚫ 结果状语从句
结果状语从句常用so that/so…that…/such…that…等来引导 so + adj./adv. + a/an + n.(单) + that such + a/an + adj./adv. + n.(单) + that such + adj./adv. + n.(复/不可数) + that eg: It’s so heavy a box that nobody can move it.
It’s such a heavy box that nobody can move it.
名词前有表示数量多少的形容词few/ a few/ little/ a little/ many/ much等修饰时，用so而不用such，但注意little有时表示的是“小” eg：Such a little animal eat so much food. 其中little表示的是“小” ⚫ 条件状语从句
条件状语从句常用if/ unless/ as(so) long as/on condition that/ provided that等来引导。可分为真实条件状语从句和非真实条件状语从句两种。
真实条件状语从句：假设的情况有可能发生的条件状语从句，主句一般用将来时，从句一般用现在时且要用陈述语气。 eg: We will come over to see you on Wednesday if we have time. 非真实条件状语从句：假设的情况发生的可能性不大或完全是一种空想的条件状语从句，从句中使用虚拟语气。
eg: If we had had more time yesterday, we could have done the work. ⚫ 目的状语从句
目的状语从句常用so(使得)/ that(以便)/ so that(为了)/ in case(以免)/ lest(以防)/ in order that等来引导，从句中常有may/ might / can / could/ should等情态动词。
eg: I will take a raincoat with me in case it rains.
⚫ 方式状语从句
方式状语从句常用as/ just as/ as if/ as though等来引导。 eg: The man carried the box away as he was told. ⚫ 比较状语从句
比较状语从句常用as…as…/ not as(so)…as/ more…than/ less…than/ the…the…等来引导，从句中常省略成分。 eg: He is not so tall as you (are).
The more we can do for you, the happier we wil be. ⚫ 让步状语从句
让步状语从句常用though/ although/ even if/ even though/ as/ whether…or…(无论)/ no matter…/ …ever等来引导。 eg: I wil go whether it rains or shines.
as引导的让步状语从句要用倒装语序且使用零冠词 Child as he is, he can answer this question. Young as he is, he knows a lot.
⚫ so that引导的结果状语从句与目的状语从句
We all arrived at eight, so that the meeting began immediately. (结果) We will come at eight so that the meeting can begin early. (目的)
① 结果状语从句一般用逗号与主句隔开，目的状语从句不； ② 目的状语从句一般含有情态动词，结果状语从句无； ③ 从句中如果有情态动词could时，两种从句都是。 He spoke loudly so that everybody could hear him. ⚫ 应避免出现双连词
eg: If I am told such a thing, and I will go too.
Because he was ill, so he couldn’t continue his work. because与so不连用
Though he was tired, but he went on working. though与but不连用，但可以与yet/ still连用
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