1、.时间状语从句.原因状语从句.条件状语从句.让步状语从句.方式状语从句.目的状语从句与结果状语从句在句子中作状语成分的从句叫状语从句。依据其含义，可分为时间、地点、原因、目的、结果、条件、让步等状语从句，下面就各种状语从句的疑难问题展开。.时间状语从句时间状语从句通常由下列连词引导：after,before,since,as,when,whenever,while,till,until,once,as soon as,scarcely(hardly)when(before),no sooner than,immediately(that),directly(that),the moment,t
2、he instant(that)等。1.as,when 和 while 都可以表示主句中动作发生的背景，也可以表示主句的动作与从句的动作同时发生。因此，在很多情况下这三个连词可以互换使用。例：example:as/when/while I was reading a book,he came into my room.虽然很多情况下可以互换，但while一词用作时间状语从句的连词时，一般不能与短暂性动词一起使用，因为while在时间概念上表示一段时间，不能表示非持续性动作。因此下列句子中的while应该改为when或as.Example:The mother was overjoyed whi
3、le she found the lost child.连词when的位置很灵活，下面两句话的意思非常相近，只是英译汉时稍有不同。Example:We were driving swiftly on the road when the car broke down.When we were driving swiftly on the road,the car broke down.2.since 用在时间状语从句中常见模式是：主句为完成时，而从句为一般过去时。其实这并不是唯一的选择。下面这些时态搭配都是可以的。Example:Since her parents died,she has li
4、ved a poor life.I havent been to the Great Wall since I have been in Beijing.Two years had passed since my daughter had married him.It seems ages since we saw him last.It has been ages since I felt happy.3.once,directly,immediately原是修饰连词that与when的副词。现在这三词已单独地引导状语从句，意义相当于as soon as，同时名词词组 the moment,
5、the instant,the minute 也可充当引导状语从句的连词。例：example:the moment the meeting is over,I will fly to New York.She wept aloud immediately she heard the news.I felt back home the instant I stepped on my homeland.4.引导词no soonerthan/hardlywhen/scarcelywhen 可以分别用来强调两个非持续性动作的同时发生。例如：Example:I had no sooner got bac
6、k to the kitchen than the door bell rang loud enough to wake the dead.5.时间状语从句的主语与主句的主语一致时，或时间状语从句的主语是不定代词it 时，这时状语从句的主语连词同动词be一起都可以省略。例：When(you are)in trouble,telephone to me.原因状语从句1.原因状语从句通常由because,since,as,now that,seeing(that),considering(that)引导。because,since,as都是引导原因状语从句的连词，其区别如下，because引导的状
7、语从句既可放在主句之前，也可置于主句之后，但置于主句之后情况居多。它所引导的原因状语从句更强调原因。而由since与as引导的从句则更强调结果，且它们多数情况下放在主句之前。Example:He was fined because he had disregarded traffic rules.As I have seen him only twice,I am afraid I may not be able to recognize him in the crowd.2.以as 引导的原因状语从句中的表语形容或名词可以移到从句之前。在正式文体中，that 可以代替连词as。例：Child
8、 as/that he was,he couldnt resist long.=since he was unarmed,he couldnt resist long.3.由because 引导的从句是状语从句，它在句中应充当状语，因此不能把它当作名词从句而在句中充当主语、宾语、同位语等。Example:Because another person lies is not the reason why you should.The reason he is absent from duty is because he is ill.条件状语从句 引导条件状语从句的连词有：if,unless,a
9、s/so long as,provided(that),providing(that),on condition(that),suppose(that),supposing(that),when,in case等。最常见的条件句，其条件分句动词用一般现在时形式，主句动词用will/shall+不定式。例如：if he doesnt come,Ill go alone.这种条件句中的条件可能实现，也可能不实现。它还可以有下列这种句式：If you wake up before lunch,give me a call.1.但是条件句并非只有这一种时态搭配。根据句意的需要，从句和主句的谓语动词可以
10、是多种时态形式。因此下面这些句子都是正确的。A：if I make a promise,I keep it.=whenever I make a promise,I keep it.B：If you heat ice,it melts.=whenever you heat ice,it melts.B：这种时态搭配的条件句用于陈述普遍真理和一般常识，或解释科学技术现象，也可以是习惯动作。此时句中的if意为whenever.有时也可以用过去时，表示过去的习惯动作。2.A：if you will reserve seats,we shall be sure of a comfortable jou
11、rney.=if you are willing to reserve seats,B:Ill cook the meal if youll do the washing up.=Ill cook the meal if you are willing to do the washing up.A,B 这种时态搭配的条件句中的will不是助动词，而是情态动词，意为“be willing to,agree to do what is suggested”.3.A:if we should miss the 10clock train,we shant get there till after l
12、unch.=if by any chance we miss the train,B:If you should die before retiring age,you widow will receive your pension for a period of 7 years after your death.=if by any chance you die,A,B 句中的条件句表示一种不太可能实现的条件。4.A：If we caught the train,we would(could,might,etc.)get there by lunch time.B:if I came int
13、o a fortune,I would give up working.A,B句中的条件句也表示很不能实现的条件。Excises:用上述句型完成下列句子。1.well just manage to catch the train if _.（我们快点）2.if I see him again,I _.（我会直接与他说）3.if my manager will lend me money,I _.（给自己买一栋房子）4.If there is a power failure,all electrical appliances_.（停止工作）5.if you should say such to
14、me,I _.（很生气）6.if I made a lot of money,I _.（去西方各国旅游）7.if we got there on time,they_.（会很高兴）8.perhaps he _ if you spoke to him yourself.（同意）9.if flowers dont get any water,they_.（马上死去）10.if you offended a dog,it_.（咬伤你）条件句有时不一定有一个引导条件句的连词，有几种特殊的句型本身就是一种隐含的条件句。其中有：祈使句+and(or)+陈述句Example:Set your alarm c
15、lock,or(else)youll oversleep.A bit more sweet food,and youll become fat.让步状语从句引导让步状语从句的连词有：although,though,even if,even though,if,granted that,granting that,when,while,whetheror,whatever,whoever,etc.,no matter what,no matter who,etc,.as,that等。1.在正式文体中，though除了可以放在句首外，也可引导这样的让步状语从句，即把主语补语或状语等放在从句之首，从
16、句通常位于主句之前。能像though一样引导这样的让步状语从句还有as和that。在这种让步状语从句中，位于句首的可以是名词、形容词、副词、动词或“动词+宾语”。Examples:Rich as/that he is,he is thrifty.Changed your mind as you may,I am determined to carry it through to the end.Hard though they worked,they could scarcely earn enough to make both ends meet.2.词尾为-ever的wh-词（如whate
17、ver,whenever）可以与“no matter+wh-词”换用，引导让步状语从句。”no matter+wh-词”比较常用于口语中。Example:Whichever alternative you choose,there wont be any real solution to the question.3.whetheror 引导让步状语从句时作“不论是否”或“不论还是”解释，谓语动词有时可用虚拟语气examples:I will do it whether you like it or not.whether be rich or poor,men should be equal
18、 before the law.4.while 引导的从句置于主句首，有时也可看作是一个让步状语从句。Examples:While I admit that the problems are difficult,I dont agree that they can not be solved.5.某些含有what或as的固定结构也可引导让步状语从句，其意义相同于词尾为-ever的wh-词。Examples:Come what may,we must remain cheerful.Say what you will,I shall still have faith in my own opin
19、ion.6.让步状语从句的主语与be可以省略，如果主语与主句主语一致，或者其主语为it时。Example:Though(we were)hungry and tired,we didnt stop working.Excises:1._as_,he continued to give comfort and first aid to the other passengers.2.every living thing,_,is made of cells.3.no matter what the cost,_.4.poor_,he is honest.5.while _,I cant agree
20、 with you.6.even though _,he refused to help me.方式状语从句 方式状语从一般由as,as if,as though引导。在非正式文体中或口语中，也可用the way(that)来引导。例：In Rome,do as the Romans do.You look as though you had seen a ghost.1.当as引导的从句位于句首时，主句常由so引出。这个so 的意思是“in the same way”。为了加强语气，又可在as前加用”just”一词。有时在主句中，可将助动词置于主语之前。Examples:As rust ea
21、ts iron,so care eats the heart.As the lion is king of beasts,so is the eagle king of birds.As fire tries gold,so does adversity try courage.2.与方式状语从句有关的习惯用法有：句首的“as it is”，句尾的”as it is“,“过去分词+as it is”,“现在分词+as it is”等四种，现分别举例说明如下：Examples:If he were not ill,he would go to see the play.As it is,he h
22、as to stay at home.You had better take the world as it is.He is my best friend,my second half,as it were.Hidden as it was by the trees,the tomb was difficult to find.Living as we do in a remote village,we rarely have visitors.3.如果方式状语从句中的主语与主句的主语相似，或者主语是不定代词it，从句中的主语与动词be也能省略。Examples:He stamped the
23、 ground as if(he was)angry.He glanced about as though(he was)in search of something.目的状语从句与结果状语从句1.目的状语从句的引导词有：in order that,so that,so,in case,for fear(that),lest等。目的状语从句中的谓语通常带有情态动词may,might,can,could,should,would等。Examples:I am saving money in order that I can go abroad for study.So arrange your
24、holiday time that you will enjoy yourself.2.引导结果状语从句的连词有：so that,sothat,suchthat,such that,that等。结果状语从句可有情态动词，也可不带情态动词。They owned another flat,so that they could invite more friends.The girl showed such great interest in music that she could play the piano at the age of four.3.目的状语从句与结果状语从句非常相似，有时很难
25、区别，特别是当两种从句都由so that引导时。要区别他们除了根据上下文来判定外，还可以从以下几个方面来分辨：1)目的状语从句通常有情态动词，而结果状语从句通常没有情态动词。We set to at once,so that the room will be cleaned out by the end of the day.Lets set to at once so that the room can(may)be cleaned out by the end of the day.2)由so that引导的目睥状语从句既可以位于主句后又可位于主句之前，而so that引导的结果状语从句只
26、能放在主句之后。So that the room may be cleaned out by the end of the day,lets set to right now.Lets set to at once so that the room will be cleaned by the end of the day.3)目的状语从句能成为一个强调句所强调的成分，而结果状语从句则不行。It is so that the room may be cleaned out by the end of the day that we should set to right now.It is s
27、o that the room will be cleaned out by the end of the day that we set to at once.4)有些结果状语从句也带有情态动词，如can，这时如何区别到底是结果状语从句，还是目的状语从句呢？唯一的区别是看有无标点符号。当从句位于主句之后时，目的状语从句通常不用逗号，而结果状语从句前通常可有逗号。Lets set to right now so that the room can be cleaned out by the end of the day.We set to at once,so that the room ca
28、n be cleaned out by the end of the day.1.things didnt go so smoothly _ we had expected.2.well set up more paper mills_ we can get enough raw material.3.the sentence comprehension exercises deal with larger units of meaning_ the other drills.4.your story of the incident would be incredible_ I had not
29、 witnessed it myself.5.a majority of women in the United States who work do so because of real economic need,not_ they want more spending money for luxuries.6._you want something done,ask a busy man.7._traffic congestion spreads,increasing amounts of time and fuel are wasted.8.supplies of canned goo
30、d and condensed milk remained low _cans had to be made by hands.9.the icebox became a fixture in most homes and remained so _ the mechanized refrigerator replaced it in the 1920s and 1930s.10.the effect of sheltering is magnified by several birds huddling together in the roosts,_wrens,brown creepers,bluebirds,and ants do.
