高考英语二轮专题总复习语法精品复合句怎样理解名词性从句、定语从句和状语从句？The question is when they won the game. 表语从句When they won the game is the question. 主语从句I have the question when they won the game. 同位语从句I wonder when they won the game. 宾语从句表语、主语、同位语和宾语通常由名词充当，所以表语从句、主语从句、同位语从句和宾语从句统称为名词性从句。
Do you know the time when they won the game? 定语从句定语通常由形容词充当，所以定语从句也叫形容词从句When they won the game, I had just finished my job. 状语从句状语通常由副词充当，所以状语从句也叫副词性从句。
结论：从句的分类是依据其在主句中的句子成分而定的。
三类从句的引导词有所不同定语从句引导词有：疑问代词和疑问副词（但不包括what和how）名词性从句引导词：①所有定语从句使用的引导词；②what和how；③少量连词：whether/if, as if/though;④以-ever结尾的疑问词：whatever, whenever等状语从句引导词有：①所有连词；②以-ever结尾的疑问词：whatever, however等定语从句引导词数量最少，状语从句引导词最多。
名词性从句引导词与定语从句引导词最接近（但范围更大），状语从句引导词与定语从句引导词差别最大。
状语从句引导词与名词性从句引导词有部分交叉（以-ever结尾的疑问词）。
另外，when 和where是这三类从句有可以使用的公共引导词。
引导词的理解定语从句引导词没有自己的字面意义，只有指代意义：指代先行词，也就是说引导词意义等于先行词词义；但名词性从句和状语从句引导词不同，它们都具有自己固定的字面意义。
Of all the books, I don’t know which is the best for me.which引导名词性从句，意为：哪一个Can you pick out the book which is the best for me?which引导定语从句，指代the bookPut the book where you can find it easily.where引导状语从句，意为：在…….地方I know where you put the book.where引导宾语从句，意为：在哪里I’ve found out the shelf where you put the book. where引导定语从句，指代the shelf但that引导名词性从句作为特例既无意义也不作句子成分，完全是“聋子的耳朵是个配佐”。
引导词的省略：一般引导词都不能省，只有极少数时候可以省略，即使可省自己造句时也最好不要省（省略形式一般看作不规范文体）。
定语从句：which/that/whom在从句中作宾语时可省，作其它成分不可省。
Can you lend me the book (that/which)you are reading? 可省Can I read the book that/which belongs to you? 不可省名词性从句：只有that引导宾语从句时可省，其它时候和其它任何名词性从句引导词都不能省(因为它们都具有特定意义)。
I know (that) he is an honest man. 可省That he is an honest man is well-known. 不可省，即使它既无意义也无成分状语从句：只有if引导条件状语从句时可省，但从句必须倒装。
If it should rain tomorrow, I would have to stay at home.= Should it rain tomorrow, I would have to stay at home.各种从句的关键之点1、定语从句①引导词的选择一定要“两看”：一看先行词是什么（人、物、时间、地点、原因等），二看先行词在从句中的句子成分。
即使同样的先行词，如果从句句子结构不同引导词就可能不同。
引导词的误用多数原因在于没有看先行词在从句中的句子成分。
提示：判断先行词在从句中的句子成分的方法是从句结构――从句缺什么成分，先行词就作什么成分，从句结构完整（什么也不缺）先行词就作状语。
I still remember the days when I lived in the countryside.lived是不及物动词，从句结构完整，先行词指时间作从句状语用when引导I still remember the days which I spent in the countryside.spent是及物动词，缺宾语，先行词虽指时间但作宾语只能用which引导②牢记只能用that的六种情况和只能用which的两种情况（非限定定语从句和在介词后）。
③把握which、as以整句为先行词的两点用法区别：一是位置上as从句可在句首、句中、句末都可以，如同状语一样，which从句只能置于句末；二是意义上，as有“正如”之意，which没有（仅指代前面的事情）。
As we had expected, they won the game. “正如”我们的预料，他们赢了= They, as we had expected, won the game.= They won the game, as we had expected.They won the game, which we hadn’t expected. 我们没有料到他们赢了④牢记what和how不能引导定语从句，只能引导名词性从句。
That’s all that I want to say.在代词all后I want to say作定语从句，用that引导That’s what I want to say.在联系动词is后I want to say作表语从句，用what引导This is the way in which/that he worked out the problem. 定语从句不能用how引导This is how he worked out the problem. 表语从句可以用how引导⑤介词﹢引导词引导定语从句时，其中的介词有没有以及用哪个介词都是由先行词与从句中的某个词（主要是谓语动词或名词或形容词等）的词语搭配关系而定的。
I like the person whom the teacher mentioned.mention是及物动词，直接构成mention the person，无需任何介词I like the person to/with whom the teacher talked.talk是不及物动词，需要介词of/with以构成talk to/with sbThe book has lots of interesting stories, of which this is one example.搭配one example of the storiesThe book has lots of interesting stories, in which he shows much interest.搭配show interest inThis is a result with which he is satisfied. 搭配be satisfied withThis is a result about which he is worried. 搭配be worried about⑥定语从句引导词的选择主要是由从句句子结构决定，主句决定是否该用定语从句以及怎样的定语从句（限定还是非限定定语从句）。
He is not the man that he used to be. 从整句看，名词后是定语从句He is not what he used to be. 从整句看，动词后是名词性从句Children love the books, which have many beautiful pictures.从整句看，逗号后面应当是非限定定语从句，只能用which引导Children love the books that/which have many beautiful pictures.从整句看，无逗号，后面应当是限定定语从句，that和which都可以2、名词性从句①掌握what从句译为名词性词组的用法。
They came to what is now called New York. 叫New York的地方②who表达疑问，whoever表达“…..的任何人”（类似what的理解）。
I don’t know who broke the door. 我不知道是哪个人打烂了门Whoever broke the door must be punished. 打烂了门的人必须受惩罚③不要混淆名词性从句和定语从句引导词确定的依据：定语从句依据“两看”而定，名词性从句依据引导词词义而定。
Do you know where he lives? 宾语从句，需要表达“在哪里”而用whereI have been to the village where he lives. 定语从句，毫无疑问之意状语从句：关键要掌握时间状语从句、条件状语从句将来时要用现在时来代替，这一点也不难，但务必辨明从句是：①状语从句还是名词性从句；②是将来时还是情态动词的运用。
When he comes, please let me know. 时间状语从句将来时用现在时来代替Please let me know when he will come. 宾语从句该用将来时If he comes, tell him I’m out. 条件状语从句将来时用现在时来代替I wonder if he will come. 宾语从句该用将来时If you will just sign here, I’ll give you the money.will作为情态动词“愿意”并非将来时2012届高考英语二轮专题总复习语法精选讲义第六部分复合句同位语从句一、在复合句中用作同位语的从句叫同位语从句。
它一般跟在某些名词后面，用以说明该名词表示的具体内容。