1、 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。 一、时间状语从句 要点: 时间状语从句,由以下连词引导:when while as after before as soon as since till /until by the time 在时间状语从句中,要注意时态一致。一般情况下主句是将来时的时候,从句要用一般现在时。1.when 当。的时候m
2、ozart started writing music when he was four years old.(当 )莫扎特的时候,开始写音乐作品。2.while 当。时he visited a lot of places while he was traveling.他在旅途中参观了许多地方。3.as 在。的同时;一边。一边。he smiled as he stood up.他一边站起来一边笑着。4.after 在。之后he left the classroom after he had finished his homework the other day.前几天做完作业之后回的家。5.b
3、efore 在。之前mr. brown had worked in a bank for a year before he came here.布朗先生来这之前已经在一家银行里工作一年了。6.as soon as 一。就。we began to work as soon as we got there.我们一到那就开始工作。i will write to you as soon as i get home.我一到家就给你写信。7.since 自。以来 到现在表示自过去的一个起点时间到目前(说话时间)为止的一段持续时间。主句一般用现在完成时,从句用一般过去时。mr green has taugh
4、t in that school since he came to china three years ago.自格林先生来中国以来,他就在这所学校教书。(还可以用作介词,本句从句还可以用短语:since three years ago(自三年前以来)表示。 )8 till /until都可以作连词,连接时间状语,也可以作介词,与其它词构成介词短语,在句中作状语。they walked till /until it was dark.他们一直走到天黑。xiao ming didnt leave home till / until his father came back.小明直到他爸爸回来才离
5、开家。9. by the time 到。为止 (所在句子的主句应用完成时)by the time he gets there , his father has already gone.他到家的时候,他爸爸已经走了。by the time i got to school, the class had already began.我到校时,已经开始上课了。难点as when while 的辨析as when while 都表示主、从句动作同时发生,三者差异如下:表示“一边。一边的意思as 强调两个动作同时进行,并表示对比时 用于发生时间较段时when 1、还可以表示从句动词的动作在主几句动词的动
6、作之前 或之后发生。2、when and then; at that moment (正在那个时候 )while 1、用于时间较长时2、 强调两个动作同时进行,并表示对比时有时这三个连词可以互换,有时不可以。lit was raining hard when (as) i got there.我到那里时,正在下大雨。 ( 动作同时发生,when 可换为 as, 但不能换为while,因为 get 是点动词.)lwhen i had read the article, he called me.我看完这篇文章之后,她给我打了电话。( 从句动作发生在主句之前,注意时态表达,只能用 when )lw
7、hen i got to the cinema, the film had begun.(当 )我到了电影院时,电影已经开演了。(从句的动作发生在主句之后,只能用 when,并要注意时态 )lhe was about to leave, when the telephone rang.他正要离开,忽然电话响了。( 此时不能放在句首。主句动词一般表达 “正在” “即将”.while, as 不能代替 ) 考点lshe thought i was talking about her daughter, while, in fact, i was talking about my daughter.
8、他以为我在谈她女儿,然而,实际上在谈论我女儿。(表转折,对比,when, as 都不能代替它) 考点lwhile the alien was buying a souvenir, the girl called the police.外星人买纪念品时,那女孩给警察打了电话。(表示主句,从句的动作同时发生,while 后引导的状语从句的动词必须是延续动词不能是点动词,因为它表示较长时间)考点lmother was worried because little alice was ill, especially as (when/ while) father was away.妈妈担心,因为小爱丽
9、丝病了,特别是他父亲不在家的时候。(此时 as ,when, while 可通用)知识扩展1. it is since 从。以来多长时间了(因为 since +从句或名词,表示一段时间)it is five years since we met last time.从我们上次见面已经五年了。2. it is +before(。才)it was a long time before i went to sleep again.过了很长时间我才睡着。it was an hour before(until) the police arrived.过了一个小时,警察才来。 二、条件状语从句要点: 表示
10、状语从句由连词 if, unless (=if not) 引导。1.if it doesnt rain tomorrow, we will go hiking.如果明天不下雨, 我们就去远足.2.you will get good grades if you study hard.如果你努力学习,就会取得好成绩.3.i will go to the party unless he goes there too.我不会去参加聚会的, 除非他也去.(如果他不去,我也不去.)4.you will be late unless you leave immediately.如果你不马上走,你将会迟到的.
11、(=if you dont leave immediately, you will be late.)难点提示:用条件状语从句时要注意时态的正确使用,当主句是将来时的时候,从句要用一般现在时.lhe will not leave if it isnt fine tomorrow.一般将来时, 一般现在时lthey are going to have a picnic if it doesnt rain next week.一般将来时, 一般现在时 考点 三、原因状语从句要点: 由连词 because, since, as 引导, 也可由 for, now that 等词引导1.i didnt
12、go to school yesterday because i was ill.我昨天没去上学,因为我生病了。2. since everybody is here, lets begin our meeting.既然大家都来了, 让我们开始开会吧.3. as you are in poor health, you should not stay up late.既然你身体不好, 你就不该熬夜.4.i asked her to stay to tea, for i had something to tell her.我请她留下来喝茶,因为我有事要告诉她.难点because , since ,
13、as , for,辨析在语气上,because 最重, 表示的是直接理由,回答 why 时只能用它. 其次是 since, as ,一般不表示原因 , 而是表明理由, 进一步说明 .(译为:由于,既然). for 被认为是复合句的并列连词(常用于推断), 表示理由.四、地点状语从句要点: 由连词 where 和复合关系词 wherever (=no matter where )引导.知识扩展1.where there is a will , there is a way.有志者事竟成。(谚语)1.it will be mixed school where not all the childre
14、n are disabled.他将是一所混合式学校,那里的儿童并不都是残疾。(在限定性定语从句中对限先行词起限定作用。)2.wherever you go , i go too.无论你到什么地方,我都去。(wherever=no matter where)无论何处,多用于句首。3.wherever there is smoke , there is fire.无风不起浪。(谚语)4. while she was wondering where to go , she met a policeman. 疑问副词 where 后跟不定式,构成不定式短语. 考点五、目的,结果状语从句要点: 目的状语
15、从句由连词 that, so that, sothat , in order that 引导。结果状语从句由连词( so )that, sothat, suchthat, so much/manythat 引导。1.sothat 如此以至于the scientists report was so instructive that we were all very excited.科学家的报告很有启发性,我们感到很兴奋。he always studied so hard that he made great progress.他总是那么努力,结果他取得了很大的进步。2.so that 以至, 以
16、便ill run slowly so that you can catch up with me. (目的)我将慢慢跑以至你能赶上我。i opened the window so that fresh air might come in. (目的)我把窗户打开以使新鲜空气可以进来。3. suchthat 如此。以至its such nice weather that all of us want to go to the park.天气是如此的好,我们大家都想去公园玩。4.in order that=so that:为了we shall let you know the details soo
17、n in order that you can/may make your arrangements.不久我们将会让你知道详情,以便你们能够做出安排。(目的)难点+形容词或副词+形 +a(an)+单数可数名词so +many 或 few+复数可数名词 +that+much 或 little+不可数名词 lso that ,suchthat 都可以 in order that 两者皆可引导目的地状语从句和结果状语从句,当他们引导目的状语从句时,从句的谓语里常常有 can, could, may, might, will, would 等次。 (见例句 2, 5 ) lso +adj./adv.+
18、 that, such +n.+ that 以上两种句型都表示结果,其中 so 为副词,后接形容词,副词原型,当可数名词前有 many, few;不可数名词前有 much, little 修饰时,应采用句型:so many (few, much, little )+n. 。 such 为形容词, 后只能接名词。这名词既可以地可数的,也可以是不可数的。如果这名词是可数,单数,则必须在名词前敬爱冠词 a(an). 常见的形式是 :such a (beautiful)garden, such(nice)people. lthe weather is so nice that id like to t
19、ake a walk. 天气是如此只好,以至于我想去散散步. lmike is so honest a man that we all believe him.麦克是如此诚实的一个人,以至于大家都相信他(=mike is such an honest man that we all believe him.) 考点live had so many falls that im black and blue all over.我跌了很多跤,浑身数摔得清一块紫一块.lthere are so few notebooks that i cant give you any.笔记本太少了,我一本也给不了你.lit is such nice weather that id like to take a walk.天气是如此只好,以至于我想去散散步. 考点六、让步状语从句要点: 表示让步的状语从句由连词 though, although 引导.难点:lthough, although 当虽然讲, 都不能和 but 连用. although,(though)but 的格式是不对的.但是他们都可以同 yet (still) 连用. 所以 thought (although)yet(still)的格式是正确的.