英语语法基础-第9讲(副词性从句).ppt

英语语法基础,第九讲 副词性从句状语从句,2,状语从句就是在复合句中起状语作用的从句。状语从句可以用来修饰动词（谓语动词或其他非谓语动词）、定语、状语，甚至整个句子。根据状语从句在句中的具体作用可以分为时间、地点、原因、目的、结果、条件、让步、方式、比较等状语从句。状语从句可以位于句首、句中或句尾。位于句首时，句末通常有逗号与主句隔开；位于句中时，从句前后须有逗号；位于句尾时，从句的前面可以不用逗号。通常，比较、方式和结果状语从句位于主句之后。状语从句一般由一个连词引导，也可由一些起连词作用的短语结构引导。,3,一、时间状语从句,时间状语从句说明动作或状态发生、存在的时间。时间状语从句可以由下列连词或词组引导。下面分别举例介绍这四类连词或词组。,4,一、时间状语从句,A.when等As time goes by,the pollution in this river is getting more and more serious.Whenever she had a cold,she ate only fruit.注：时间状语置于句首时，后面要有逗号与主句分开。B.before等He will go to study abroad after he graduates from the college.I have not seen him since he left the company.注：until 经常与not连用，notuntil表示一个固定意思，直到才。He didnt announce the news until he was sure of it.Go straight ahead until/till you reach the post office.注：在时间状语从句中，不用将来时。,5,一、时间状语从句,C.as soon as等We will leave the minute he is ready.Every time he comes to see us,he brings us some candies.D.hardlywhen 等：hardlywhen,scarcelywhen，no soonerthan的意思一样，但在使用时，要注意它们的搭配。hardly，scarcely分别和when连用，no sooner和than连用，不能调换。I had hardly sat down when the telephone rang.注：hardly，scarcely，no sooner位于句子开头时，句子的主、谓语要倒装。Scarcely had the noise died away when someone started to laugh again.,6,二、地点状语从句,地点状语从句说明动作或状态发生、存在的地方。地点状语从句由where（在的地方）和wherever（无论在的地方）引导。Keep the medicine where children cannot see it.You can camp wherever you like these days.,7,三、条件状语从句,条件状语从句说明动作或状态发生、存在的条件。条件状语从句由下列连词或词组引导。下面分别举例介绍这三类连词或词组。,8,三、条件状语从句,A.if 和unless We shall have a picnic if it is a fine day tomorrow.Id like to go swimming unless the water is too cold.=Id like to go swimming if the water is not too cold.B.as(so)long as 等 As long as we dont lose heart,well find a way to overcome the difficulty.In case the car burns down,well get the insurance money.C.suppose/supposing 等 Supposing he doesnt agree,what will you do?Providing there is no objection,we shall make a decision.注：在条件状语从句中，不用将来时。,9,四、原因状语从句,原因状语从句说明动作或状态发生的原因。原因状语从句由because（因为），since（因为），as（因为），now that（既然），seeing(that)（因为），considering that（鉴于，考虑到）等连词或词组引导。Seeing that she doesnt like piano,there is no reason to make her learn it.Considering(that)he is only 10 years old,he really did a good job.,10,五、结果状语从句,结果状语从句说明动作或状态发生后所产生的结果。结果状语从句由sothat，suchthat（如此以至于），so that（结果）等连词或词组引导。We left in such a hurry that we forgot to lock the door.The moon was so bright that the flowers were bright as by day.注：suchthat 之间只能用名词，sothat之间只能用形容词，但是在形容词后可以加一个名词。He is such a strong man that he can lift that heavy box.He is so strong that he can lift that heavy box.He is so strong a man that he can lift that heavy box.,11,六、目的状语从句,目的状语从句说明发生这一动作、行为的目的。它由that，so that，in order that（以便，为了），lest（以免），for fear that（惟恐），in case（以防）等连词或词组引导。,12,六、目的状语从句,A.that，so that，in order that：在(so)that，in order that引导的目的状语从句中，一般需要情态动词。主句是一般现在时，从句要用can或may。主句是一般过去时，从句要用could或might。当so that引导的从句是否定句时，要用should。We must try to increase the competitive in order that we may make more profits.The police asked me to move it off the road(so)that it might not hold up the traffic.注：so that既可以引导结果状语从句，又可以引导目的状语从句，区别在于：目的状语从句中要有情态动词can，may，should等，so that 前没有逗号。结果状语从句不用情态动词，so that 前常有逗号。,13,六、目的状语从句,B.lest，for fear that，in case：在 lest，for fear that引导的从句中，一般用should+动词原形，should可以省略。In case 引导的从句一般用虚拟语气（should+动词原形），也可用真实语气。She explained again and again lest the students(should)misunderstand her.Here is some money in case you(should)need it.Take a hat with you in case the sun is very hot.,14,七、方式状语从句,方式状语从句说明动作、行为发生的方式。方式状语从句由as（与一样），as if（好像），as though（好像，仿佛）等引导。I did the thing as you told me.It looks as if it is going to rain.He walks slowly as though he were sick.注：as if，as though意思相同，可以互换使用。as if，as though引导的从句多用虚拟语气。但如果说的事情可能是事实，也可以用真实语气。,15,八、比较状语从句,比较状语从句是对人、事物的特征、性状和数量等进行比较。带有比较状语从句的句型有：,16,八、比较状语从句,A.（形容词、副词）比较级+than（比）My handwriting is much worse than yours.She sings better than I(me).注：比较级前可有much，far，a bit等次说明比较的程度，也可以有数字说明具体的差距，如：She is two years older than I.B.as+（形容词、副词）原级+as（和一样）The article in todays newspaper is as important as that in yesterdays newspaper.You should remember as many words as you can.You should keep as much money as you can.You should read as much as you can.,17,八、比较状语从句,C.not+so+（形容词、副词）原级+as：He is not so tall as his brother.This job is not as difficult as that one.D.倍数+as+（形容词、副词）原级+as（是几倍）Your stadium is ten times as big as ours.This auto manufactory made twice as many cars this year as they did last year.注：表示倍数时，2倍是twice，绝不可以用two times。三倍以上用数字加times，如：four times，five times等。倍数必须放在asas结构之前。E.the+比较级，+the+比较级（越，就越）I like black coffee so much,the stronger it is,the better I like it.The harder you study,the more knowledge you can gain.,18,九、让步状语从句,让步状语从句由下列连词或词组引导，下面举例介绍这三类连词或词组：,A.though，although，as/while：（1）though和although两个单词本身就表示“虽然，但是”，所以绝对不能再和but连用。They are my relatives though I dont know them.Although it was difficult to find a job,yet people moved to cities where there were many factories.,19,九、让步状语从句,A.though，although，as/while：（2）as也可用引导让步状语从句，意思与though/although相同。但是，用as引导让步状语从句，通常放在句首，且主谓要倒装。as前面的词可以使形容词、副词，也可以是动词、名词。Rich as he is,he is not happy.Child as he is,he knows a lot.（此时名词前一定不能有冠词）Try as/though he might try,he couldnt move this stone.=Although he might try,he couldnt move this stone.（3）while 引导让步状语从句，只能放在句首，意思与though/although相同。While I fell sympathetic,I really cant do anything to help them.While he may be right,we dont agree him to do it.,20,九、让步状语从句,B.even if/though Even though its hard work,I enjoy it.His finger print can prove who he is even if his appearance has been changed by age or accident.C.however等,We must begin testing this instrument,no matter how(=however)difficult it is.No matter where(=Wherever)you are,I shall be with you.No matter who(=Whoever)you are,you should pay your tax.No matter which(=Whichever)you like,take it away.No matter what(=Whatever)you do,try to do it better.,