课件20张PPT。第十九节 状语从句一、 状语从句的定义 用一个句子(从句)来作另一个句子(主句)的状语，用作状语
的句子就叫作状语从句。作什么样的状语就叫什么类型的状语
从句。如条件状语从句就是用一个句子来作条件状语。二、状语从句的分类1. 时间状语从句，通常由when, while, as, before, after,till/until, as soon as 等词引导。(1)when 意为“当……时”，引导的时间状语从句表示主句的动作和从句的动作同时或先后发生。如：I feel very happy when you come to see me.你(们)来看我时，我感到很高兴。When you are crossing the street, you must be careful. 你( 们)过街道时，一定要小心。when 引导的时间状语从句中，可以用延续性动词，也可以用短暂性动词。如：He was working at the table when I went in.当我进去的时候，他正在桌旁工作。(短暂性动词)Someone knocked at the door when I was sleeping. 当我正在睡觉时，有人敲门。(延续性动词)I will visit my good friend when I arrive.当我到达时，我将去看望我的好友。(短暂性动词)I worked for a foreign company when I was in Shanghai.当我在上海时，我为一家外国企业工作。(延续性动词)注意：when 也可以作并列连词，表示一个动作正在进行的时候，突然间发生了另外一件事。如：I was fishing by the river, when someone called for help.我正在河边钓鱼，就在那时有人求救。We were working in the chemistry lab, when the lights wentout.我们正在化学实验室工作，突然灯都熄灭了。 (2)while 意为“当……时”“在……期间”，引导的时间状
语从句表示主从句的动作在同一时期发生，常用延续性动词或
表示状态的词。如：They rushed in while we were discussing problems.当我们正在讨论问题时，他们冲了进来。Father was cleaning the car while I was playing computergames.当我正在玩电脑游戏时，爸爸正在清洗汽车。
注意：while 也可以作并列连词，表转折的关系，相当于but，译为“然而”。如：I like listening to music, while my brother likes doing sports.我喜欢听音乐，而我的兄弟爱好运动。(3)as 意为“当……时”“一边……一边……”， 主从句动作同时发生。如：As they walked, they talked happily.他们一边走，一边高兴地交谈着。(4)before 意为“在……之前”，引导时间状语从句时，表示主句的动作发生在从句的动作之前。如：We cleaned the classroom before we left school yesterday. 昨天离开学校之前，我们打扫了教室。He had been a cook before he went to college.他上大学前曾当过厨师。(5)after 意为“在……之后”，引导时间状语从句时，表示主句的动作发生在从句的动作之后。如：After you use plastic bags, you mustn't throw them about. 你(们)用过了塑料袋之后，不准到处乱扔。He called me after he had finished his work.他在工作完之后给我打了个电话。 注意：若主句和从句两个动作发生的先后顺序十分接近，
那么也可以不用完成时态，如上面的第二句可改成：He calledme after he finished his work.(6)since 引导的时间状语从句，表示“自从……”，主句常用现在完成时，从句常用一般过去时。如：We have made many dumplings since we began to cook.自从我们开始做饭起，我们已包了许多饺子。We haven't seen each other since we parted.我们自从分手以后一直没见过面。注意：常用句型“it is ＋时间段＋since 从句”意为“自从……有多长时间了”。如：It is six years since she graduated from the university.自从她大学毕业已有六年的时间了。 (7)until 意为“直到……时”。当主句的谓语动词是持续性
动词时，主句常用肯定形式；当主句的谓语动词是非持续性动
词 时 ， 从 句 常 用 否 定 形 式 ， not...until... 意为“ 直到……
才……”，这时的 until 可以用 before 来替换。如：I'll stay here until you come back.我会待在这里，直到你回来。(stay 表示的动作可以持续) He didn't go to bed until/before he finished his homework. 他
直到做完作业才睡觉。(go to bed 表示的动作不能持续)
(8)as soon as 意为“一……就……”，表示从句的动作一发生，主句的动作马上就发生。如：I'll tell him about it as soon as he comes back.他一回来我就告诉他这件事。 2.条件状语从句，主要由 if, unless, as long as 等引导。我们
主要看一下由 if 引导的条件状语从句。if 意为“如果”，引导
一般条件状语从句时，主句用将来时，从句用一般现在时。如：
If it doesn't rain tomorrow, we will go there by bike.如果明天不下雨，我们就骑自行车去那里。If I get there early, I can see the doctor quickly.如果我早早地到那里，我就可以快点看病。3.地点状语从句，常用 where (哪里)和 wherever (无论哪里)引导。如：Where there is a will, there is a way.有志者，事竟成。We will go wherever the motherland needs us most.我们要到祖国最需要的地方去。 4.原因状语从句，常用的引导连词有 because (因为), as (由
于)和 since (既然)。三者的区别是：在回答问题的时候，使用
because；对于显而易见的原因，常用 as 或 since；as 和 since 的
从句常放在主句之前，而 because 的从句常放在主句之后。如：—Why did you go？你为何去？—I went because Tom told me to go.那是因为汤姆叫我去。
As it was raining hard, we had to be indoors.由于雨太大，我们只好待在家里。Since you feel ill, you'd better not go to work. 既然你感觉不舒服，你最好不要去上班了。 5.目的状语从句，常用的引导连词有 so that 和 in order that，
意为 “以便，为了，目的是”，从句中常需用情态动词，so that
从句只能放在主句之后。如：Please speak more slowly so that we can make full notes.请讲慢一点，以便我们能作完整的笔记。I shall write down your address so that I may not forget. 我要把你的地址记下来，以免忘记。I sent the letter by air mail in order that it might reach him intime.这封信我以航空信发出，以便他能及时收到。注意：目的状语从句可以用动词不定式， in order to, so asto 来替换作目的状语。如：We work harder than usual so that we can finish it in a week.＝We work harder than usual to finish it in a week.＝We work harder than usual in order to finish it in a week.
＝We work harder than usual so as to finish it in a week.我们比平常加倍努力工作，以便在一周内完成工作。6.结果状语从句，常由“so...that...” “such...that...”(如此……以致……)引导。如：He is so short that he can't reach the apple.他太矮了，够不到那个苹果。It is such a heavy box that I can't move it.这是个很重的箱子，我搬不动它。7.方式状语从句，常由 as (如，像)，as if (好像)引导。如：
Please do as what I told you.请按照我所告诉你的做。8.让步状语从句，常由 although, though (虽然，尽管)引导。如：
Though he was very tired, he didn't stop working. 尽 管 他 很累，他没有停止工作。一、主句与从句时态一致的问题在时间状语从句和条件状语从句中，主句和从句之间的时态一致问题一般分下列两种情况： 1.若主句是祈使句，或主句中有情态动词，或主句中谓语动
词是一般将来时，那么从句用一般现在时表示一般将来时。如：Be careful when you cross the road.过马路时要小心。Put up your hand if you have any questions to ask. 如果你们有任何问题要问的话，请举手。The traffic must stop when the lights are red.红灯亮时，车辆必须停下。2.若主从句谓语动词都是陈述过去，那么主从句都可以用一般过去时。如：She could sing when she was four years old.她四岁的时候就会唱歌。二、if 的不同用法 if 有两个意思，作“是否”讲时，引导宾语从句，意同
whether，从句的时态由事实决定；作“假如，如果”讲时，引
导条件状语从句，此时若主句为将来时或祈使句时，从句用一
般现在时。如：If it rains, we won't have a sports meeting.如果下雨，我们就不开运动会了。三、when 引导的时间状语从句和宾语从句 1.含有 when 引导的时间状语从句的复合句中，若主句是一
般将来时，从句应用一般现在时；when 引导其他时态的时间状
语从句时，从句时态应与主句时态保持一致。 2.when 引导的宾语从句，首先要保证从句的陈述句语序，
然后再根据主句的时态确定从句时态，使其基本与主句内容保
持意义上的一致。如：I don't know when my father will come back, but I'll tell youwhen he comes back.我不知道我爸什么时候回来，但是当他回来
时我会告诉你。四、when, while 和 as when, while 和 as 引导的从句都可以使用延续性动词。when,
as 还可以与终止性动词连用，而 while 则不能。when 可表示瞬
间、时间段，表示从句与主句所叙述的动作、事情可同时发生，
也可有先后。while 用于表示同时进行的两个延续性动词相伴随
而发生，常对同类的两个动作进行比较。as 不指先后，而指并
列发生，尤指两个动作或事件同时发生。如：The film had been on when we arrived.我们到达时电影已放映。My mother was cleaning the room while I was doing myhomework.我做作业时，妈妈在打扫房间。As I left the house, I forgot the key.我离开家时把钥匙忘了。第十九节 状语从句
( )1.(2013年孝感，27)—We can't be successful ________ we keep working hard.
—I agree with you.
A．if B．unless C．because D．when
( )2.(2013年丹东，40)—What are you doing tomorrow, Jane?
—I'll go bike riding if it ________.I like riding on rainy days.
A．doesn't rain B．is cloudy C．is snowy D．rains
( )3.(2013年营口，9)If my brother ________ well in his exams, he'll go to Tsinghua University next September.
A．did B．does C．is doing D．will do
( )4.(2013年雅安，14)If farmers ________ trees and forests, giant pandas ________ nowhere to live.
A．cut down; have B．will cut down; will have
C．will cut down; have D．cut down; will have
( )5.(2013年宁波，35)—Have you finished your project?
—Not yet.I'll finish it if I ________ ten more minutes.
A．give B．am given C．will give D．will be given
( )6.(2013年南宁，33)I will wait ________ I hear from you.
A．until B．since C．while D．because
( )7.(2013年梅州，37)—Mr.Li ________ to Mary carefully when I entered the classroom this morning.
—He is very patient ________ he is young.
A．talking; but B．was talking; though
C．talks; though D．talked; however
( )8.(2013年广东，36)If Nancy ________ the exam, she will go to Australia for English study.
A．pass B．passed C．passes D．will pass
( )9.(2014年佛山，23)I am writing to you________ I'm afraid to talk about it face to face.
A．because B．though C．until
( )10.(2014年广东，41)—I wonder whether Brazil will win the match later tonight.
—Go to bed first.I will wake you up as soon as the match ________.
A．starts B．started C．will start D．is starting
( )1.________ there were only five soldiers left at the front, ________ they went on fighting.
A．Because; so B．If; and C．Though; but D．Though; /
( )2.________ she is very old, ________ she can still work eight hours a day.
A．Because; so B．Though; but C．As; yet D．Though; yet
( )3.Fortunately, they found that they hadn't waited long ________ the police came to help them.
A．before B．after C．while D．unless
( )4.Three years has passed________ we left school.
A．after B．since C．until D．when
( )5.It's quite common in Britain to say “Thank you.” to the drivers ________ people get off the bus.
A．after B．until C．when D．since
( )6.We should go by bus________ we can get there earlier.
A．as soon as B．where C．in order that D．as
( )7.The book is ________ interesting ________ I like to read it a second time.
A．such; that B．too; to C．as; as D．so; that
( )8.—Where was your brother at this time last night?
—He was writing an e-mail ________ I was watching TV at home.
A．as soon as B．after C．until D．while
( )9.Now many parents send their children to foreign countries, ________ they want them to get a better education.
A．until B．though C．because D．so
( )10.He has________ an interesting book that we want to read it.
A．so B．such C．the same D．as
( )11.It was________ that we all wanted to go for a picnic.
A．such fine weather B．a fine weather
C．so fine a weather D．such a fine weather
( )12.When you want to ________， please remember this saying “________ there is a will, there is a way.”．
A．give up; / B．give up; Where C．give in; Where D．give in; /
( )13.Just as we________ school, it began to rain.
A．leave B．had left C．were leaving D．left
( )14.—I wonder if he ________ us in the discussion tonight.
—I believe if he ________ his homework, he will join us.
A．will join; will finish B．will join; finishes
C．joins; finishes D．joins; will finish
( )15.I will let you know about it as soon as I ________ the news.
A．will get B．gets C．got D．get
第十九节 状语从句
真题·体验感悟
1—5 BDBDB 6—10 ABCAA
演练·巩固提升
1—5 DDABC 6—10 CDDCB 11—15 ABDBD
