复合句就是由一个主句和一个或一个以上的从句构成。主句为句子的主体，从句不能独立，只能作全句的一个句子成分，需要通过从属连词、关系代词、关系副词、连接副词等与主句连接起来。中考主要会考查的是宾语从句、定语从句和状语从句。
一、宾语从句，天下谁人不识君
首先请看部分中考真题：
1．－Could you tell me _____ the Bamboo Garden?
－The day after tomorrow, I think.
A. when will you visit B. when you will visit
C. when would you visit D. when you would visit
2．－Do you know _______ Mr Green will come?
－Yes, I think he will come.
A. What time B. where C. how D. whether
3.I heard that she was singing at that time. （改为简单句，保持句意不变）
答案：1. B，2. D，3. I heard her singing at that time.
结论：1．如果主句是一般过去的时态，宾语从句则也要用表示过去的时态——但表客观事实、科学真理等仍要用一般现在时。
2．由一般疑问句改为宾语从句时要注意加关联词if或whether，由特殊疑问句改为宾语从句时不要丢下连接代词和连接副词，表示一般疑问意义和特殊疑问意义的宾语从句，其语序与陈述句的语序相同，即主语在前，谓语动词在后。
3．含“是否、有否”等一般疑问意的宾语从句，由从属连词if或whether作关联词；而示“谁、谁的、什么、哪个、什么时候、什么地方、怎样、为什么等”特殊疑问意义的宾语从句，所用的关联词相当于特殊疑问句中的疑问代词who，whom，whose，what，which和疑问副词when，where，how，why——这时它们称作连接代词和连接副词，这类宾语从句有时还用whoever，whatever，whichever等合成词引导。
4. 含宾语从句的复合句多数能在保持句意不变的前提下，进行简化——这可是中考命题老师们喜欢的特别“小甜点”——首当其冲，用不定式替换宾语从句；略施小计，把宾语从句改作名词（短语）；见机而作，让宾语从句改为“宾语 现在分词或过去分词或形容词（作宾语补足语）”；特殊手法，把宾语从句变身为“V-ing形式”。
二、状语从句，生活有你更精彩
（一）时态呼应
1．复合句一般都会遵循主、从句时态呼应规律，状语从句也不例外：即主句用现在时，从句也用现在时；主句用过去时，从句也用过去的某种时态。如：Be careful when you cross the road.
2．主句是一般过去时，从句也要用一般过去时。例如：My brother could swim when he was seven years old.
3．但状语从句有一个怪脾气：如果主句是一般将来时态，从句偏不用将来时态，而用一般现在时替代。例如：I won't go there if it’s rainy tomorrow.
（二）宾从、状从并肩战，if与when巧分辨
不少中考题故意将“宾从”与“状从”混合考，这时要引起注意的是：①从句式看，宾语从句只能放在主句谓语动词之后，而状语从句一般可以放在主句的前面或后面；
②从引导词看，if充当宾语从句的引导词时，与whether“同谋”，为“是否”，而引导条件状语从句，充当从属连词时，为“如果、倘若”；when充当宾语从句的连接词时，词义为“什么时候/何时”，充当从属连词，引导时间状语从句时，词义为“当……的时、当时”；
③从时态看，if和when作连接词，引导宾语从句时，其谓语动词的时态应根据主句的谓语动词的时态作相应的变化，if和when充当从属连词，引导表示将来动作或状态的条件状语从句或时间状语从句时，若主句中的谓语动词用了一般将来时，则从句中的谓语动词通常用一般现在时表示将来。如：I don't know if it will rain tomorrow. 与If it rains, I will not go fishing. →I don't know if it will rain tomorrow. If it rains, I will not go fishing.
同理，“Do you know when he will come tomorrow?”与“When he comes, please let me know.”也常同时“合二为一”考！
（三）句型转换或连词考查
⒈until、till“直到”，引导时间状语从句——当主句谓语动词是延续性动词时，主句常用肯定形式；当主句谓语动词是非延续性动词时，主句要用否定形式，即“not ... until / till ...”意为“直到……才……”。例：
You can't go home until / till you finish your work.
但许多时候的until、till可与after/before/as soon as/if等词相置换。如：
As soon as/If/When/After Jane leaves here, I'll post the letter to Mike. = I won’t post the letter to Mike until/before Jane leaves here.
⒉条件状语从句有一个知心朋友，这个朋友有时可以替代条件状语从句及其主句，它就是大家熟悉的“祈使句 and/then/or 简单句”——其中and/then表句意顺接；or则表转折，意为“否则、要不然（的话）”。例如：
If you walk faster, you'll catch the early bus. = Walk faster, you'll catch the early bus.
If you don't hurry up, you'll miss the early bus. = Hurry up, or you'll miss the early bus.
注：if…not=unless，所以上例又常与Unless you hurry up, or you'll miss the early bus. 异曲同工。
三、定语从句，我的美丽你会懂
被定语从句修饰的名词或代词叫先行词，定语从句必须放在先行词之前，引导定语从句的词有连词that，关系代词who，whom，whose，which，关系副词when，where，why。如：
1. Winter is the time of year_____ the days are very short and cold.
A. when B. that C. where D. on which （选A）
2. 一Is the girl ______ is interviewing the manager of that company your friend?
一Yes，she is a journalist from CCTV.
A. whom B. which C. who D. whose （选C）
下面几种情形一般只用that：①当先行词为all，much，little，few，nothing 等不定代词时；②当先行词有no，any，all，much，little，the only，the very，the same，the last等词修饰时；③当先行词由序数词或形容词最高级修饰时；④当先行词既有人又有物时。如：
1. I’m a football fan. I’m interested in everything ________ is about the 2006 World Cup.
A. who B. that C. where D. what （选B）
2. All _____ they have done is harmful for health.
A. what B. which C. why D. that （选D）
不看不知道，一看原来初中英语教材中（或中考）有那么多简化了的定语从句：放眼简化后的定语从句，理解起来特别亲切——下例中考实录就是最好的证明（答案为C）：
—What are on show in the museum?
—Some photos_____ by African children.
A. are taken B. were taken C. taken D. have been taken
⒈爱作定语形容词短语能“顶定语从句的班”。如：
Please help me carry the box which is full of new books to the classroom →Please help me carry the box full of new books to the classroom.
⒉用相应的介词短语把定语从句“换下”。如：
The shoes that lie on that shelf are very popular these days. →The shoes on that shelf are very popular these days.
⒊不定式（短语）要来作定语，定语从句常“让位”。如：
Is there anything else that we should do next? →Is there anything else for us to do next?
⒋现在分词（短语）要来独自作定语，定语从句只好“下课”。如：
The boy who is reading under that big tree is my good friend Jack.→The boy reading under that big tree is my good friend Jack.
⒌作定语的过去分词短语与相应的定语从句“兑换”。如：
The man whom we name Lao Zhang is Li Lei’s uncle.→The man named Lao Zhang (by us) is Li Lei’s uncle.
