(完整版)高中英语状语从句讲解和练习(含答案).docx
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完整版)高中英语状语从句讲解及练习状语从句是指在句中作状语的从句,可以分为时间、条件、让步、原因、目的、结果、比较、地点、方式状语从句。
时间状语从句的连词有when、as、while、until、not…until、before、after、since、the minute、the moment、each、every、next、the first time等。
时间状语从句一般使用一般现在时或一般过去时。
当使用when、as、while这三个连词引导时间状语从句时,它们都表示“当…的时候”,但侧重点有所不同。
例如,当使用when引导时间状语从句时,从句的主语与主句主语相同,如果谓语动词是be动词,则从句主语和be可以省略。
而as则不仅表示“当…的时候”,还可以表示“一面…一面”或“随着”。
而while则强调主句的动作和从句的动作同时发生,从句一般用进行时,从句动词必须是延续性动词。
当使用until、not…until时,它们表示“直到…才”。
在肯定句中,主句常用延续性动词;在否定句中,主句常用短暂性动词。
需要注意的是,当not until…位于句首时,主句需要倒装。
例如,“Not until you had explained how did I manage to do it.”It was dark when he finally returned。
XXX the machine type upon seeing it。
As soon as I arrived home。
it began to rain。
Hardly had I arrived home when it began to rain。
XXX: real XXX: if。
even if/though。
unless/if。
not。
as long as/so long as。
as far as/so far as。
provided/providing(that)。
高考英语三大从句讲解+练习(附答案)【名词性从句】名词性从句相当于名词,可分别作主句的主语、表语、宾语和同位语。
因此,名词性从句成分为主语从句、表语从句、宾语从句和同位从句。
(一)引导名词性从句的连接词1、连接代词:who, whose, whom, what, which。
有词义,在从句中担任成分,如主语、表语、宾语、或定语等。
2、连接副词:when, where, why, how。
有词义,在从句中担任成分,作状语。
3、连接词:that, whether, if, as if。
that 无词义,在从句中不担任成分,有时可省略;if (whether), as if虽有词义,但在从句中不担任成分。
1. 主语从句作句子主语的从句叫主语从句。
主语从句通常由从属连词that,whether,if和连接代词what,who,which,whatever,whoever以及连接副词how,when,where,why等词引导。
that在句中无词义,只起连接作用;连接代词和连接副词在句中既保留自己的疑问含义、又起连接作用,在从句中充当从句的成分。
例如:What he wants to tell us is not clear. 他要跟我们说什么,还不清楚。
It is known to us how he became a writer. 我们都知道他是如何成为一名作家的。
Where the English evening will be held has not yet been announced.英语晚会将在哪里举行,还没有宣布。
有时为避免句子头重脚轻,常用形式主语it代替主语从句作形式主语放于句首,而把主语从句置于句末。
主语从句后的谓语动词一般用单数形式。
常用句型如下:(1)It + be + 名词+ that从句(2)It + be + 形容词+ that从句(3)It + be + 动词的过去分词+ that从句(4)It + 不及物动词+ that 从句另注意在主语从句中用来表示惊奇、不相信、惋惜、理应如此等语气时,谓语动词要用虚拟语气“(should) +do”,常用的句型有:It is necessary (important, natural, strange, etc.) that …It is a pity (a shame, no wonder, etc.) that…It is suggested (requested, proposed, desired, etc.) that…注意:连词that, whether在从句中不担任句子成分,只起连接作用,不能省略。
WORD格式可编辑状语从句(一)状从句概述定状从句用作状,是起副作用的句子。
位置状从句可以放在主句之前,也可以放在主句之后,、条件、原因和步状从句放在句首需要用逗号和主句隔开。
分根据其作用可以分、地点、原因、条件、目的、步、方式和比等状从句。
作用它可以修、非、定、状和整个句子。
(二)状从句解1.状从句引用法when意“当⋯的候”。
When引从句的可以是延性,也可以是瞬。
并且 when有表示“就在那”while 意“在⋯的候,在⋯的同”。
While 引从句的必是延性的,生,并主句和从句的作同生(或者相)。
While有可以表示比。
as 意“一⋯一⋯”。
As引的作是延性的,生短,一般用于示例A liar is not believed when he speaks the truth. 者真也没有人相信。
Whenhe arrives, I ’ll call you.When you laugh and smile, your body relaxes.While I was standing at the window, I saw several boys running along the street. While John was watching TV, his wife was cooking.The writer was angry as he was travelling on a train to London because someone had主句和从句作同invaded his “space”.生;as 也可以一前一He smiled as he stood up.后。
after 意“在⋯之后”。
表示主With many hungry visitors 句作生在从句作之waiting, don’t stay too后。
主句与从句的作long at your table after you关系与 before 引的have finished.从句相反。
状语从句讲解和练习状语修饰动词、形容词、副词或整个句子。
通常由副词、介词短语、动词不定式、分词和从句等担当。
例如:1. Nat urally , our grandparents wer e pleased to get our phone call . (副词)2. We worked ha rd , from sunrise to sunset . (介词状短语)3. To help my d isabled aunt , I spend an ho ur working in her house ever y day . (不定式)4. Seen from a distance , the farmhouse l ooked deserted . (过去分词)5. I know how to light a ca mp fire because I had done it before .(原因状语从句)状语的位置比较灵活,可以位于句首、句末或句中。
enough用作状语修饰形容词和副词时必须后置。
状语从句主要用来修饰主句或主句的谓语。
一般可分为九大类,分别表示时间、地点、原因、目的、结果、条件、让步、比较和方式。
尽管种类较多,但由于状语从句与汉语结构和用法相似,所以理解和掌握它并不难。
状语从句的关键是要掌握引导不同状语从句的常用连接词和特殊的连接词即考点。
现分别列举如下:1.时间状语从句常用引导词:when, as, while, as soon as, while, before, after, since , ti ll, until特殊引导词:the minute, the moment, the sec ond, every time, the day,the instant, immediately , directly, no sooner … than, hardly …when, scarcely… whenI didn’t realize how special my mother wa s until I became an adult.While John was watching TV, his wife was cooking.The children ran away fr om the orchard(果园) the moment they saw the gu ard.No sooner had I arrived home than it began to rain.Every time I listen to your advice, I get into t rouble.2.地点状语从句常用引导词:where特殊引导词:wherever, anywhere, everywhereGenerally, air will b e heavily polluted where there are factories.Wherev er you go, you should work hard.3.原因状语从句常用引导词:because, since, as, since特殊引导词:seeing that, now that, in that, considering that, given tha t, considering that, My friends dislike me because I’m handsome and successful.Now that everybody has come, let’s begin our conference.The higher i ncome tax is harmful in that it may discourage pe ople from trying to earn more.Considering that he is no more than 12 years old, his height of 1.80 m is quite remarkable.4.目的状语从句常用引导词:so that, in order that特殊引导词:lest, in case, for fear that,in the hope that, for the purpose that, to the end thatThe boss asked the secretary to hurry upwith the letters so that he could sign them.The tea cher raised his voice on purpose that the students in the back could hear more clearly.5.结果状语从句常用引导词:so … that, so… that, such … that,特殊引导词:such that, to the degree that, to the extent t hat, to such a degree that,He got up so early that he caught the first bus.It’s such a good chance t hat we must not miss it.To such an degree was he excited that he coul dn’t sleep last night.6.条件状语从句常用引导词:if, unless, 特殊引导词:as/so long as, only if, providing/provided that, suppose that, in case that, on condition that We’ll start our proj ect if the president agrees.You will certainly succeed so long as you keep on trying.Provided that there is no opposition, we shall hold the meeting here. 7.让步状语从句常用引导词:though, although, even if, even though特殊引导词:as(用在让步状语从句中必须要倒装),while ( 一般用在句首),no matter (i)spite of the fact that, while, whatever, whoever, wh erever, whenever, however, whicheverMuch as I res pect him, I can’t agree to his proposal. 尽管我很尊敬他,我却不同意他的建议。
时间状语从句用句子表达一件事情或一个行为发生的时间,这个句子就叫时间状语从句。
时间状语从句根据其所表示的时间不同,所使用的连词也不同。
下面我们一起来看一下几个常见的时间状语从句:1. when 引导的从句:表示主句的动作和从句的动作同时发生,或从句的动作发生在主句动作之前。
例如:I was going out when a visitor came. (动词动作同时发生。
)我正要出门,有客人来访。
I shall tell her the good news when she comes.她来时,我将告诉她这个好消息。
小试牛刀:I found mother cooking for me. I got home.(when)He was listening to the radio when I home. (get)2. while 引导的从句:表示“当……过程中”,强调某一段时间内主句和从句中谓语动词所表示的动作在同一时期发生。
由于while 从句表示一个持续的行为,所以从句中要用持续性动词,并且持续性动词常用进行时态。
例如:Keep an eye on my little sister while I am away.我不在时,请照看一下我的小妹妹。
While we were watching TV, Jim came in. 我们看电视的时候,Jim 进来了。
小试牛刀:It started to rain. We were playing football.(while)Lucy was cleaning the room Lily was listening to music.3. as 引导的时间状语从句:表示“当……的时候;一边……一边……;随着……”,其从句的主语与主句的主语往往是同一人或物。
例如:She sang as she worked. 她一边工作一边唱歌。
=She was singing as she was working.I saw him as he was getting off the bus. 正当他下公共汽车时, 我看见了他。
高中英语状语从句专项讲解及练习(有答案)状语从句1、地点状语从句地点状语从句表示地点、方位,这类从句通常由where, wherever, anywhere, everywhere引导。
Where there is a will, there is a way.有志者,事竟成。
They will go where they are happy.他们想到他们觉得快乐的地方去。
We must camp where we can get water. 我们必须在能找到水的地方露营。
地点状语从句与定语从句的区别:在于分句在句中作什么成分。
作状语,则是状语从句;作定语修饰名词,则是定语从句。
where引导定语从句时,从句前应有一个表示地点的名词作先行词;而状语从句前则无需先行词。
如:Go back where you came from.(where引导地点状语从句)Go back to the village where you came from.(where引导定语从句,修饰village)We went home, where we had dinner. (where引导定语从句,修饰home)2、原因状语从句原因状语从句一般由because(因为),since(既然),now that(既然,因为),as(由于)等连词引导。
(1)because表示直接的原因,表示原因的语气最强,常表示必然的因果关系。
回答why引起的特殊疑问句,只能用because。
Jane wore a raincoat because it was raining.因为天下雨,所以詹穿着雨衣。
He is absent today because he is ill.他今天缺课,因为他病了。
(2)since表示对方已经知晓、无须加以说明的原因或事实,语气比because稍弱。
I'll do it for you since you are busy.既然你忙,我来替你做吧。
高考英语状语从句40题附答案1.—Wha.ar.yo.goin.t.d.thi.summer?—I'm going to visit the Great Wall __________ the school term ends.A.s.tha.B.a.soo.as.C.before.D.i.orde.that2.M.Englis.i.ver.poor..can'.lear.i.wel._________.yo.hel.me.A.if.B.unless.C.while.D.when3..wa.tol._____puters.A.tha.ho..B.ho.tha..C.whe.tha..D.tha.when4.—D.yo.hav.an.problem.i.yo._______.fiv.minute.t.read?—Well.I'.thinkin.abou.th.ne.words.Ther.ar.to.many.A.giv..B.give..C.ar.give..D.wer.given5.His father has worked for 17years in this factory __________ he came here in 2000.A.since.B.for.C.whenD.ho.long6.Thi.lesso.wa.s.borin.___.som.student.bega.t.slee.i.class.A.that .B.and .C.when .D.how7.You can make progress in English __________ you try your best.A.befor.B.unless.C.whether.D.a.lon.as.8._______.h.ha.littl.knowledge.th.ol.worke.ha..lo.o.experience.A.I.B.Becaus..C.Althoug.D.when9.I will lend you my computer you promise to return it on time.A.sinc..B.whe..C.o.conditio.tha..D.i.orde.that10..tru.frien.ca.se.th.pai.i.you.eye.____.everyon.els.believe.th.smil.o.you.face.A.whil..B.becaus..C.befor..D.until11.Th.movi.i..grea.success._________.it'.no.ver.good.A.s..B.bu..C.althoug..D.and12.Jac.was’.sayin.anything,bu.th.teache.smile.a.hi.. h.ha.don.somethin.ver.clever.A.in caseB.as ifC.wileD.though13.I.th.exam.th._______.yo.are.th.______.mistake.yo.wil.make.A.careful.littl..B.mor.careful.fewes..C.mor.careful.fewe..D.mor.careful.less14.Thi.i.a.interestin.book...... I’l.bu.it... .A.ho.muc.ma.i.cos..B.howeve.i.ma.cos.C.ho.ma.i.cos....D.n.matte.ho.i.ma.cos.15.Today we will begin we stopped yesterday so that no point will be left out.A.whenB.whereC.howD.what16.—Does Ted tell you if he __________ next Sunday?—No.h.doesn't.Bu.i.h.________.I'l.giv.yo..ring.e...e..e17.Th.bu.drive.alway.say.t.u.,“Don'.ge.off_______.th.bu.stops.”A.whe...B.whil.....unti...D.i.18.Yo.spea.i..lo.voice.Danny.Pleas.spea.loudl.____..ca.hea.yo.clearly.A.thoug..B.s.tha..C.bu..D.unless19.____ you keep on trying, I really don’t mind whethe.you can come up top in your class.A.As long asB.Even thoughC.As soon asD.The moment20..Yesterda.ther.were ... .man.peopl.i.th.par.... .almos.los.m.way..I.wa.th.Ma.Da.holiday.Lot.o.peopl.wante.t.hav.fu.there.A.quite.that .B.very.tha.C.enough.that .D.so.tha.21..won'.believ.you__..hav.see.i.wit.m.ow.eyes...A.befor..B.unti..C.afte..D.when22.Some people are holding their umbrellas ____ it is raining.A. in caseB.so thatC.as thoughD.unless23.—We'l.g.fo..picni.i.i._______.thi.Sunday.— Wish you a lovely weekend.A.rai..B.rain..C.won'.rai..D.doesn'.rai.24.—You speak _____ fast _____ we can’t follow you.—I will speak slowly.A.so.that .B.such.tha.C.suc.a.tha.D.too.to25.Sh.__.hom.__.sh.wa.satisfie.__.hi.answe.yesterday...A.didn'.go.until.t....B.wasn'.g o.after.t...C.doesn'.go.before.wit..D.didn'.go.until.with26.There are always ____interesting stories in the series that ___ many people watch them.A. so.so .B.such.suc..C.such.so ..D.so.such27.we won’t change our plan, it rains.A.becaus..B.sinc..C.a.i.D.eve.i.28.Yo.shoul.finis.you.lesson.______.yo.g.ou.t.play.A.befor.B.afte.C.whe.D.while29.Projec.Hop.ha.raise.muc.mone._________.th.poo.childre.ca.g.t.school.A.because.B.s.tha..C.i.orde.to.D.though30.Teres.i._______.nervou._______.sh.can'.tal.i.fron.o.th.class.A.such.tha..B.too.t..C.so.tha..D.too,that31.These days the long TV play is popular my mother often keep watching it for twohours without a rest a day .A.such.that .B.to..t..C.ver..that .D.s..that32.Th.meetin.didn'.start__.everyon.wa.there.A.becaus..B.unti..C.wh..D.if33.Stayin.i..hote.cost.... rentin..roo.i.a.apartroo.fo..week.A.twice as more asB.as more twice asC.twice as much asD.as much twice as34.H.too.of.hi.coa.______.h.fel.hot.A.becaus.B.a.C.i.D.since35._________.afte.th.dail.har.work.M.Ya.wa.hungr.fo.books.A.Tire.a.wa.h..B.A.tire.h.wa..C.A.h.wa.tire..D.Tire.a.h.was36.Whe.yo.rea.th.book.you’.bette.mak..mar.______.yo.hav.an.questions.A.whic.B.tha.C.wher.D.though37._________ hamburgers are junk food, __________ many children like them.A.Although...B.Although.bu..C.Because...D.Because.so38.Literature must consist of words, music sonsist of sounds.A.even thoughB.so thatC.just asD.even sincet.fo.clas.yesterda.______.ther.wa.somethin.wron.wit.m.bike.A.whe.B.tha.C.unti.D.because40..Th.docto.tol.m.no.t.ea.to.much.bu..foun.i.difficult.—Th.docto.i.right.________.yo.eat._____.yo.wil.be.A.Th.less.th.healthie...B..Th.less.th.mor.healthilyC.Th.more.th.healthie..D.Th.more.th.mor.healthily1~5BBDCA 6~10ADCCA11~15CBCBB 16~20ACBAD21~25CADAD 26~30CDABC31~35DBCAD 36~40CACDA。
状语从句由从句担任的状语,在句子中可修饰谓语(或其它动词)、形容词、副词或是整个句子,它可以用来表示时间、地点、原因、目的、结果、条件、方式、比较、让步等。
第一讲时间, 地点状语从句时间状语从句:when, while, as, before, after, since , wheneveruntil, till, by the time(注意时态)as soon as, had hardly…when, had no sooner…than, (on doing sth…)the moment, every time/ each time, the first time, oncee.g: When he came, I had cleaned the classroom.He didn’t stop working until his mother came bake.He worked until his mother came back.As soon as he returned, he bought a new flat.He had no sooner returned than he bought a new flatHe came to scene the moment he heard the news.I thought her nice and honest the first time I met him.Once he makes up your mind, he won’t change his min d.It was two years before I met him again. = Two years passed before I met him again.注意点1. when引导的从句动词可以是延续性的或短暂性的,while引导的从句中动词必须是延续性的;while有时并不表示时间,而表示对比,表示“而”、“却”。
高考英语专题复习状语从句(附答案)I. 考点分析状语从句可用来表示时间、地点、原因、目的、结果、条件、方式、比较和让步等。
1.时间状语从句1) 常见关联词有when, whenever, while, as, before, after 等。
2)注意not…until… 正常结构、倒装结构、强调结构、和until置于句首的用法。
He didn’t go to sleep until he had finished his homework. (正常结构)Not until he had finished his homework did he go to sleep. (倒装结构)It was not until he had finished his homework that he went to sleep.(强调结构)Until he had finished his homework he didn’t go to sleep. (until置于句首)3)表示“一……就……”的连词:once, as soon as, hardly/scarcely…when, no sooner…than, the minute, the moment, the instant, immediately, directly, instantly4)其他表示时间的短语还有:every time, next time, the day 等。
2.地点状语从句通常由where, wherever引导如:Where there is a will, there is a way.3.原因状语从句1) 通常由because, as ,since引导, 三者区别:because 语气最强,重在交待原因,以why引导的疑问句只能because用来回答;其前可用only, just等词强调;可用在It is…that…强调句型中。
状语从句讲解及习题附答案word文档良心出品(一)状语从句概述(二)状语从句详解1.时间状语从句引导词用法示例whe n 意为“当…的时候” When A liar is not believed when 引导从句的谓语动词可以he speaks the truth. 说谎者讲是延续性动词,也可以是真话时也没有人相信。
瞬间动词。
并且when有When he arrives , I 'call you.时表示“就在那时”When you laugh and smile,your body relaxes.while 意为“在??的时候,在…的While I was standing at the 同时” While引导从句的window, I saw several boys谓语动词必须是延续性running along the street.的,发生时间较长,并强调主句和从句的动作同时发生(或者相对应)。
While有时还可以表示对比。
as 意为“一边…一边…” As引导的动作是延续性的,发生时间较短,一般用于主句和从句动作同时发生;as也可以强调一前一后。
after 意为“在??之后”表示主句动作发生在从句动作之后。
主句与从句的动作时间关系与before引导的从句相反。
before 意为“在??之前”引导的从句不用否定形式的谓语,并且当before引导的从句位于主句之后,有时译成While John was watchingTV, his wife was cook ing.The writer was angry as hewas travelling on a train to London because someonehad inv aded his sp ace ”.He smiled as he stood up.With many hungry visitors waiting, don' stay too longat your table after you havefini shed.If an early exit is n ecessary, you can leave after a sceneis over.You can ' watch TV beforeyou finish your homework. Before it ended, the theatre was almost empty.“就才”当主句用将来时,My father had left for Ca nada意为“自从,从??以来”引since I have been studying hardI will call you as soon as Iarrive.2. 地点状语从句引导词用法示例where意为“哪里。
状从句解和状修、形容、副或整个句子。
通常由副、介短、不定式、分和从句等担当。
例如:1. Naturally , our grandparents were pleased to get our phone call . (副 )2.We worked hard , from sunrise to sunset . (介状短 )3.To help my disabled aunt , I spend an hour working in her house every day . (不定式 )4.Seen from a distance , the farmhouse looked deserted . (去分 )5.I know how to light a camp fire because I had done it before .(原因状从句)状的位置比灵活,可以位于句首、句末或句中。
enough用作状修形容和副必后置。
状从句主要用来修主句或主句的。
一般可分九大,分表示、地点、原因、目的、果、条件、步、比和方式。
尽管种多,但由于状从句与构和用法相似,所以理解和掌握它并不。
状从句的关是要掌握引不同状从句的常用接和特殊的接即考点。
分列如下:1.状从句常用引: when, as, while, as soon as, while, before, after, since , till,until特殊引: the minute, the moment, the second, every time, the day,the instant, immediately , direc tly, no sooner ⋯ than, hardly ⋯ when, scarcely ⋯ whenI didn ’realizet how special my mother was until I became an adult.While John was watching TV, his wife was cooking.The children ran away from the orchard(果园 ) the moment they saw the guard. Nosooner had I arrived home than it began to rain.Every time I listen to your advice, I get into trouble.2.地点状从句常用引: where特殊引: wherever, anywhere, everywhereGenerally, air will be heavily polluted where there are factories.Wherever you go, you should work hard.3.原因状从句常用引: because, since, as, since特殊引: seeing that, now that, in that, considering that, given that, considering that, Myfriends dislike me because I ’ mhandsome and successful.Now that everybody has come, let ’begins our conference.The higher income tax is harmful in that it may discourage people from trying to earn more. Considering that he is no more than 12 years old, his height of 1.80 m is quite remarkable.4.目的状从句常用引: so that, in order that特殊引: lest, in case, for fear that,in the hope that, for the purpose that, to the end that The boss asked the secretary to hurry up with the letters so that he could sign them.The teacher raised his voice on purpose that the students in the back could hear more clearly.5.果状从句常用引: so ⋯ that, so⋯ that, such ⋯ that,特殊引: such that, to the degree that, to the extent that, to such a degree that, He gotup so early that he caught the first bus.It ’such a good chance that we must not miss it.To such an degree was he excited that he couldn ’sleept last night.6.条件状从句常用引: if, unless,特殊引: as/so long as, only if,providing/provided that, suppose that, in case that, on condition thatWe’ ll start our project if the president agrees.You will certainly succeed so long as you keep on trying.Provided that there is no opposition, we shall hold the meeting here.7.步状从句常用引: though, although, even if, even though特殊引:as(用在步状从句中必要倒装),while ( 一般用在句首),no matter⋯,in spite of the fact that, while, whatever, whoever, wherever, whenever, however, whicheverMuch as I respect him, I can’agreet to his proposal.尽管我很尊敬他,我却不同意他的建。
The old man always enjoys swimming even though the weather is rough.No matter how hard he tried, she could not change her mind.He won’ tlisten whatever you may say.8.比状从句常用引: as(同比 ), than(不同程度的比 )so⋯; A is to B what /as X is to Y; no⋯mo 特殊引: the more ⋯ the more ⋯ ; just as ⋯,re than; not A so much as BShe is as bad-tempered as her mother.The house is three times as big as ours.The more you exercise, the healthier you will be.Food is to men what oil is to machine. 食物之于人,犹如油之于机器。
9.方式状从句常用引: as, as if, how特殊引: the wayWhen in Rome, do as the Roman do.She behaved as if she were the boss.Sometimes we teach our children the way our parents have taught us.10.状从句的化?状从句的省略状从句同具下列两个条件 :①主句和从句的主一致,或从句主it ;②从句主要是be 的某种形式。
从句中的主和be 常可省略。
例如:When ( the museum is ) completed , the museum will be open to the public next year .He’ ll go to the seaside for his holiday if (it is ) possible.另外,比状从句常省略。
例如:I ’ mtaller than he (is tall ).The higher the temperature (is), the greater the pressure (is ).就状从句而言 ,有了使言言意 ,常常将状从句行 "化 "。
状从句的 "化 "象在口中普遍 ,而且在高考中的复率也高。
因此 ,有必要其行全面、透的了解。
状从句的 "化 " 象常存在于以下五种状从句中:①由 if, unless等引的条件状从句 ;②由 althoug h, though, even if / though 等引的步状从句 ; ③由 when, while, as, before, after, until / till 等引的状从句 ;④由 as, as if 等引的方式状从句 ;⑤由 as, than 等引的比状从句。
下面五种情形作一。
(1)当状从句的主是it,且是 be ,it 和 be 要完全化掉。
例如 :If (it is) possible, he will help you out of the difficulty. 如果可能的 ,他会帮你脱困境。
You must attend the meeting unless (it is) inconvenient to you.除非情况你来不方便,否你必出席这次会议。
(2)当状语从句的主语和主句的主语一致时,从句可以将主语和be 动词简化掉。
常用于以下几种情形:a.连词 +形容词As (he was) young, he learned how to ride a bike.他小时候就学会了骑自行车。
Whenever (she is) free, she often goes shopping.她有空就去逛商店。