高中英语主要要掌握三大从句。分别是：1、定语从句（形容词从句）2、名词词从句（包括主语从句，宾语从句，表语从句，同位语从句）3、状语从句（副词性从句，包括时间，地点，结果，目的，原因等）一、定语从句：定语从句（Attributive Clauses）在句中做定语，修饰一个名词或代词，被修饰的名词,词组或代词即先行词。定语从句通常出现在先行词之后，由关系词（关系代词或关系副词）引出。1、关系代词引导的定语从句 关系代词所代替的先行词是人或物的名词或代词，并在从句中充当主语、宾语、定语等成分。关系代词在定语从句中作主词保持一致。（1）, who, whom, that这些词代替指人，“whom”作宾语指人，“that”既可作主语又可作宾语（作宾语可以省略），可以指人也可以指物。（2），Which 用来指人或物(用作主语、宾语，作宾语时可以省略）（3），whose“whose”表示谁（可以为人也可以为物）的（东西）2、关系代词引导的定语从句（1），关系副词why主要用于修饰表示原因的名词（主要是the reason），同时它在定语从句中用作原因状语。（2），关系副词when主要用于修饰表示时间的名词，同时它在定语从句中用作时间状语。（3），关系副词where主要用于修饰表示地点的名词，同时它在定语从句中用作地点状语。3、非限制性定语从句它起补充说明作用，缺少也不会影响全句的理解。在非限制性定语从句的前面往往有逗号隔开。二、名词性从句 在句子中起名词作用的句子叫名词性从句 (Noun Clauses）。 名词性从句的功能相当于名词词组, 它在复合句中能担任主语、宾语、表语、同位语、介词宾语等，因此根据它在句中不同的语法功能，名词性从句又可分别称为主语从句、宾语从句、表语从句和同位语从句。 引导名词性从句的连接词可分为三类：1、连词（5个）：that （宾语从句或表语从句中that有时可以省略） whether,if （均表示“是否”表明从句内容的不确定性） as if ,as though （均表示“好像”，“似乎”） 以上在从句中均不充当任何成分2、连接代词（9个）：what, whatever, who, whoever, whom, whomever, whose, which, whichever3、连接副词（7个）：when, where, how, why, whenever, wherever, however三、状语从句 状语从句 （Adverbial Clause） 状语从句指句子用作状语时，起副词作用的句子。它可以修饰谓语、非谓语动词、定语、状语或整个句子。根据其作用可分为时间、地点、原因、条件、目的、结果、让步、方式和比较等从句。状语从句一般由连词(从属连词)引导，也可以由词组引起。从句位于句首或句中时通常用逗号与主句隔开，位于句尾时可以不用逗号隔开。状语从句细分的话，共包括九种： 1.时间状语从句2.地点状语从句3.原因状语从句4.条件状语从句5.目的状语从句6.让步状语从句7.比较状语从句8.方式状语从句91. Mary lives in the room, the door _ opens east. A. of it B. of which C. of that D. whose 2. The engineer _ my father is talking has just come from abroad. A. with whom B. with who C. with which D. that 3. He lives in a hotel, _ is only five minutes walk from here. A. that B. which C. in which D. where 4. Is there anything _ I can do for you? . A. which B. who C. as D. that 5. The speaker will tell us about some writers and their works _are known to us. A. which B. that C. as D. who 6. This is the reason _ they are all against the plan. A. which B. that C. why D. what 7. It was not until late in the evening _ the traveler found a hotel. A. which B. that C. as D. where 8. I didnt like the way _ she spoke to me. A. which B. that C. how D. as 9. This is _ I can do for you right now. A. which B. that C. what D. as 10. It was at our college library _ I borrowed the novel. A. which B. in which C. that D. where 11. I have seen trees, _ open at sunrise and close at sunset. A. which the leaves B. of which leaves C. whose leaves D. its leaves 12. All _ is needed is a supply of oil. A. the thing B. that C. what D. which 13. The foreign guests, _ were scientists, were warmly welcomed at the airport. A. most of whom B. most of them C. most of which D. most of those 14. On the train I saw a student _ I thought was your sister. A. who B. whom C. which D. that 15. Is the river _ through the town very long? A. flows B. that flows C. which flow D. the one flows 16. Is this college _ they went to last year? A. that B. which C. the one D. the one what 17. Is this the university _ you visited last time? A. that one B. which C. the one D. the one what 18. Id like to tell you _ I saw in the exhibition. A. which B. that C. what D. / 19. I hope that the little _ I have been able to do has been of some use. A. which B. that C. what D. for which 20. Who _ has common sense will do such a thing? A. which B. that C .whose D. whom 21 The bike and its rider _ had knocked down the boy were taken to the police. A. who B .that C. which D. whom 22. Put the letter _ he can find it easily. A. in which B. at which C. where D. which 23. This is the very letter _ I am looking for . A. which B. that C. as D. what 24. Tom didnt attend the meeting, _ we expected. A. where B. that C. as D. what 25. I will give you such information _ will help you. A. which B. that C. as D. what 26. This is the best hotel in the city _ I know. A. which B. that C. where D. it 27. The lady _ is a woman scientist. A. whom you spoke B. with which you spoke C. whom you said to D. you spoke to 28. This is the third week _ the dustmen havent come for the rubbish. A. that B. when C. which D. on which 29. He is the only one of the students _ the truth. A. who know B. who knows