英语专业四级考试语法词汇知识点讲解:复合句

　　复合句名词性从句

　　一个句子起名词的作用，在句中做主语、宾语/介词宾语、表语、同位语，那么这个句子就是名词性从句。

　　1.what/whatever的用法 考生应把握：what是关系代词，它起着引导从句并在从句中担当一个成分这两个作用。如：

　　They lost their way in the forest， and what made matters worse was that night began to fall.

　　Water will continue to be what it is todaynext in importance to oxygen.

　　2.whoever和whomever的区别

　　whoever和whomever相当于anyone who，用主格与宾格取决于其在从句中做主语还是做宾语。如：

　　They always give the vacant seats to whoever comes first.

　　3.有关同位语从句的问题

　　引导词通常为that， 但有时因名词内容的需要，也可由whether及连接副词why， when， where， how引导。that不表示任何意义，其他词表示时间、地点、原因等。如：The problem， where I will have my college education， at home or abroad， remains untouched.

　　同位语从句有时与先行词隔开，注意识别。如：

　　Evidence came up that specific speech sounds are recognized by babies as young as 6 months old.

　　4.whether与if在引导名词性从句时的区别

　　主语从句只能用whether引导;

　　whether一般多用于宾语从句的肯定式，而if引导的从句可以有否定式;

　　whether or not可以连在一起用，而if or not则不能，or not只能放在句末;

　　whether可以引导介词宾语从句，if则不能;

　　宾语从句提至谓语前面时，只能用whether引导;

　　在question， ask后面一般只用whether，question的同位语从句也用whether引导;

　　后接不定式时，只能用whether。

　　5.动词believe， expect， fancy， imagine， suppose， think后的宾语从句如为否定式，一般将否定词转移到主句谓语上。

　　复合句副词性从句

　　副词在句中起状语作用，故如果起状语作用的部分为一个句子，那么该句便是副词性从句，也称状语从句。状语从句可细分为：时间、地点、条件、原因、让步、目的、结果、比较、方式等。

　　状语从句的测试重点为：考查考生对主从句之间逻辑意义关系的把握，看其是否能选择正确的从属连词。

　　1.条件状语从句的常考知识点

　　if与unless的用法。if和unless都是引导条件状语从句的连词，考生应尤其注意unless的用法，因为它表示反面条件，相当于if not如果不、除非。如：In debating， one must correct the opponents facts， deny the relevance of his proof， or deny that what he presents as proof， if relevant， is sufficient.

　　复合连词as long as，so long as，as far as，on condition that，in the event that;动词及分词provided，providing，given that， suppose/supposing，assuming，say等引导条件状语从句。如：

　　You can arrive in Beijing earlier for the meeting provided you dont mind taking the night train.

　　Assuming he is diligent in his studies at ordinary times， he is sure to pass the test.

　　In the event that she has not been informed， I will tell her.

　　You can go swimming on condition that you dont go too far from the river bank.

　　Suppose it rained， we would still go. Say it were true， what would you do about it?

　　祈使句表示条件。如：Dress warmly， or else youll catch cold.

　　Talk to anyone in the drug industry， and youll soon discover that the science of genetics is the biggest thing to hit drug research since penicillin was discovered.

　　2.让步状语从句的常考知识点

　　as 引导让步从句，要求用倒装结构，把强调的部分置于句首。如：Much as he likes her， he does get irritated with her sometimes.

　　Humble as it may be， there is no place like home.

　　while引导让步从句。如:

　　Everybody cheats a little， some psychologists say， while others insist that most people are basically honest and some wouldnt cheat under any circumstances.

　　复合连接词for all that和分词granting/granted引导让步从句。如:

　　Granted you have made much progress， you should not be conceited.

　　For all that computers can provide us with great help， they shouldnt be seen as substitutes for fundamental thinking and reasoning skills.

　　3.时间状语从句的常考知识点

　　before表示汉语的 只有/必须才能。如: New ideas sometimes have to wait for years before they are fully accepted.

　　when引导时间从句时，如果出现在后半句，则表示这/那时突然。如：

　　I have just started back for the house to change my clothes when I heard the voices.

　　when it comes to 是习惯用法，意为当谈到时。如：

　　Doing your homework is a sure way to improve your test scores， and this is especially true when it comes to classroom tests.

　　名词短语、介词短语each /every time， the moment/second/minute， in the time， by the time起连词作用。如:

　　I hope her health will have improved greatly by the time we come back next year.

　　My pain must have been apparent the moment I walked into the room， for the first man I met asked sympathetically: Are you feeling all right?

　　Mercurys velocity is so much greater than the Earths that it completes more than four revolutions around the Sun in the time it takes the Earth to complete one.

　　副词directly， immediately， instantly， now引导时间从句， 相当于as soon as。如:

　　The policemen went into action directly they heard the alarm.

　　4.原因状语从句的常考知识点

　　in that引导原因从句时，有时翻译成是因为、就在于。如:

　　Advertising is distinguished from other forms of communication in that the advertiser pays for the message to be delivered.

　　Criticism and self-criticism is necessary in that it helps us to find and correct our mistakes.

　　now that表示 既然 seeing that， considering表示鉴于、考虑到。如:

　　Now that we have all the material ready， we should begin the new task at once.

　　He did poorly in the examinations， considering how hard he had tried for them.

　　Seeing that she is lawfully old enough to get married， I dont think you can stop her.

　　其他引导原因状语从句的连接词语还有: for the reason that， by reason that， on the grounds that， in as much as， in so far as等。

　　5.while， whereas 引导对比从句

　　如: While the teenage population in the United States has declined over the past decade， violent crimes committed by juveniles have sharply increased.

　　A baby might show fear of an unfamiliar adult， whereas he is likely to smile and reach out to another infant.

　　6.sothat， with the result that， so much so that 引导结果状语从句

　　如: Over the years， a large number of overseas students have studied at that university with the result that it has acquired substantial experience in dealing with them.

　　He himself believed in freedom， so much so that he would rather die than live without it.

　　7.in order that， in case， for fear that， lest 引导目的状语从句

　　如: Give me your telephone number， in case I need your help.

　　Helen listened carefully in order that she might discover exactly what John wanted.

　　8.where作为连接副词的一种用法， 翻译为在地方

　　如: In Japan， a persons capabilities are not forced into an inflexible specialty. Where there is willingness and intelligence， there is a place within the company to try and to succeed.