高一英语同步精品课件：MODULE 2 DEVELOPING AND DEVELOPED COUNTRIES - GRAMMAR（外研版必修3）.ppt

1、1charity1)n.C,U慈善机构We all support a charity to help the tsunamihitcountries.我们都捐钱给一个慈善机构来帮助遭海啸袭击的国家。2)n.U 慈悲；仁爱；慈善I think that is what we should do out of charity.我认为那是我们出于仁爱所应该做的。知识拓展charitable adj.仁慈的；(为)慈善事业的；宽厚的uncharitable adj.严厉的；无情的；不宽厚的即学即用完成句子Many _ sent money to help the victims of famine.

2、许多慈善机构捐款赈济饥民。答案：charities2crowded adj.拥挤的；挤满人的The place is crowded.这地方很挤。The buses are so crowded during the rush hour.高峰时间公交车非常拥挤。The robbery occurred in a crowded street.在拥挤的大街上发生了抢劫。搭配be crowded with 挤满了The room was crowded with guests.房间里挤满了客人。The bus was crowded with passenagers.公共汽车里挤满了乘客。知识拓展

3、crowd n.C人群 v.聚集，拥挤A crowd of people were waiting in front of the gate.一大群人在门前等着。The children crowded the cinema waiting for their favourite film.孩子们挤满了电影院等着看他们最喜爱的电影。词语辨析a crowd,the crowdThere is/are a crowd of people over there.那边聚集着很多人。The crowd was/were dispersed.人群被驱散了。a crowd“许多人”，作主语时谓语动词可以是单

4、数(指集合体)，也可以是复数(指成员)。the crowd“民众，大众”，意同the public；作主语时谓语动词可以用单数，也可以用复数。3freeway n(motorway)高速公路知识拓展free pass n.免费出入证freebie n.免费赠品free port n.免税港；自由港freestyle n.(游泳等)自由式即学即用英译汉a freeway exit _to get into the freeway _答案：高速公路出口 进入高速公路4inhabitants n.C居民，住户，常住居民；栖息的动物The local inhabitants protested at

5、the plans for an airport.当地居民强烈反对兴建机场的计划。This kind of birds is the new inhabitants on this island.这种鸟是该岛新的栖息动物。知识拓展inhabit vt.居住于；存在于；占据；栖息inhabitable adj.适于居住的；可居住的inhabitability n.可居住的状况inhabitation n.居住；有人居住的状态即学即用汉译英这是一个有11000居民的城镇。_答案：This is a town of 11000 inhabitants.5industrial adj.工业的Engla

6、nd is an old industrial country.英国是一个古老的工业国家。Industrial development is concentrated in the northeast.工业发展集中在东北部。词语辨析industrial,industrious知识拓展工业、农业、商业：6transport1)n.U运输The transport of goods by air is very expensive.空运货物十分昂贵。2)n.U交通(系统)；运输(系统)Our public transport system is among the best in our coun

7、try.我们的公共交通系统在我们国家是一流的。3)n.U交通工具；运输途径Id like to go to the concert,but I have no transport.我想去听音乐会，但我没有交通工具。4)v.运输；运送Trains transport the coal to the port.火车把煤运到港口。词语辨析transport与traffictransport作“交通”讲，实指运输工具，而traffic之“交通”指街上的行人车马，着重数量的多少。故“交通拥挤；交通中断”中的交通都用traffic一词。(误)Transport is interrupted in many

8、 places.(正)Traffic is interrupted in many places.(译)很多地方交通中断了。知识拓展transporter n.输送人；运输机transportation n.运输；运送transportability n.可运输性；应处以流放transportable adj.可运输的；(计算机)便携式的即学即用完成句子The women _ _ _ a nearby hospital for treatment.这些妇女被送到附近一家医院接受治疗。答案：were transported to7smart adj.整洁漂亮的；时髦的；洒脱的You look v

9、ery smart in that new shirt.你穿那件新衬衫看上去很帅。Do you think he is as smart as she says?你认为他真像她所说的那样聪明吗？She always wears smart dresses.她总是穿着时髦的服装。知识拓展smartness n.漂亮；潇洒smartly adv.潇洒地；漂亮地；火辣辣地；刺痛地smarten v.使漂亮潇洒词语辨析smart,bright,clever与wise1)smart强调“调皮；很帅”，用于口语。2)bright多指年轻人或小孩，常用于口语中，书面语中不常用。3)clever应用范围很广，

10、指人或动物时，通常表示“脑子灵”；用于物时，常含有“巧妙”之意。4)wise侧重具有丰富的经验、广博的学识、正确的判断力和处理能力，含有“深谋远虑”的意思。即学即用Nowadays the young like wearing _ clothes.AsmartBbrightCclever Dwise答案：A8vast adj.巨大的；广大的；巨额的；广阔的The vast plains stretch for hundreds of miles.辽阔的平原绵延数百英里。The doctor was brought from Beijing at vast expense.这位医生是花高薪从北京

11、请来的。词语辨析vast,hugeHospitals keep vast supplies of drugs.医院储备了大量的药品。In the huge library,books upon books,lie against the walls.在那间大图书馆里，挨墙摆着大量的书。vast 强调(二维)空间的广度，指范围的广和数量的大，侧重于面积的极为开阔，不强调重量或尺寸大小。huge强调体型、尺寸大小，不强调重量。即学即用填空vasthugeThere is a _ balloon here.I saw the _ lawns surrounding the white house.答

12、案：hugevast1collect money for：raise money for 为捐款集资Were trying to collect money for the victims of the earthquake.我们正在设法为地震受灾者筹集资金。知识拓展earn/make money 挣钱；赚钱save money 攒钱charge money 收费put money into 投资于pay good money for.为花大钱即学即用Little Johnny felt the bag,curious to know what it _.Acollected Bcontain

13、edCloaded Dsaved答案：B2make宾语宾补This didnt make them move or retreat.这没有使他们动摇或退缩。Praise makes good men better and bad men worse.赞扬使好人更好，坏人更糟。When you speak English,be sure to make yourself understood.说英语时一定要让人懂得你的意思。They have decided to make Shanxi Province a large coal base.他们决定把陕西建成一大型煤炭基地。知识拓展make宾语

14、domake宾语donemake宾语adj.make宾语n.注意：在“主语make宾语do”结构中，要变为被动语态，省略的不定式符号“to”要写出。They thought in this way they could make us take their orders.They thought in this way we could be made to take their orders.他们认为这样就可以使我们听他们发号施令了。高考直击(2010辽宁33)The fact that she was foreign made _ difficult for her to get a jo

15、b in that country.A.soB.much C.that D.it 解析：句意：她是外国人的事实使得她在那个国家很难找到工作。考查it的用法。句中for her to get a job in that country是动词不定式的复合结构做made的宾语，difficult是宾语补足语，此处要用it做形式宾语，其他词没有这种用法。答案：D即学即用He is very popular among his students as he always tries to make them_in his lectures.Ainterested BinterestingCinteres

16、t Dto interest答案：A3as manypl.as.与一样多的Madame Curie became interested in physics and read as many books as she could on the subject.居里夫人对物理很感兴趣，并尽可能多地阅读了有关物理方面的书籍。This year this factory produced as many cars as it did last year.今年这家工厂生产的汽车与去年一样多。知识拓展1)as much(n.)Uas.与一样多的as many aspl.n.多达多少I havent ma

17、de as much progress as I should.我没有取得应有的进步。He ate as much rice as he could.他放开肚子大吃了一顿米饭。As many as twenty members have already left.有20名会员离开了。There are as many as ten million copies of books in our library.我们图书室拥有的图书竟多达10 000 000册。I have as much as 20 dollars.我有多达20美元。2)asadj./adv.as 与一样的；达多少Her fac

18、e is as white as snow.她的脸像雪一样白。Tom runs as fast as Mary.汤姆和玛丽跑得一样快。The tree is as high as 20 metres.这棵树高达20米。高考直击(2009辽宁)Peters jacket looked just the same as Jacks,but it cost_his.Aas much twice as Btwice as much as Cmuch as twice as Das twice much as 解析：考查倍数的用法。正确的顺序为：倍数as形容词或副词as.答案：B即学即用John is

19、the tallest boy in the class,_according to himself.Afive foot eight as tall asBas tall as five foot eightCas five foot eight tall asDas tall five foot eight as答案：B连 词(一)连词的定义用来连接词、短语、从句与句子的词叫连词。连词是一种虚词，在句中不重读，不能独立担任句子成分。根据在句中所起的作用，连词可分为并列连词和从属连词两类。(二)并列连词连接具有并列关系的词、短语或句子的连词叫并列连词。根据其意义，并列连词又可分为表示联合、转

20、折、选择和因果四种关系的连词。1表示联合关系的并列连词表示联合关系的并列连词有：and(和)；both.and.(既又)，neither.nor.(既不也不)，not only.but also.(不但而且),as well as(除外也)。They can both read English and speak it well.他们能读英语而且说得很好。Neither you nor he is wrong.你和他都没有错。He not only had read the book but also remembered what he had read.他不仅读了那本书，而且还记得读过的内

21、容。I am a teacher and he is a doctor.我是老师，他是医生。He has experience as well as knowledge.(He has not only knowledge but also experience.)他既有知识，又有经验。Neither I nor he has seen the film.我没看过这部电影，他也没看过。2表示转折关系的并列连词表 示 转 折 关 系 的 并 列 连 词 有：but(可 是，但 是);while(而，然而)；still(但是，然而)；yet(可是);however(然而，但是);whereas(而

22、);nevertheless(然而，不过)。I am willing,yet unable.我心有余而力不足。He is short,while his brother is tall.他个子矮，然而他兄弟个子高。He worked hard,however,he failed.他很努力，然而还是失败了。The pain was bad,still he did not complain.他痛得厉害，可是他并没有呻吟。3表示选择关系的并列连词表示选择关系的并列连词有：or(或);or else(否则);otherwise(要不然);either.or.(或或；不是就是)；rather than

23、(而不，也不)。I must work hard,or Ill fail in the exam.我得认真学习，否则不能通过考试。Either you or I am to blame.不是你就是我会受到批评。You can either do it by yourself,or you can ask someone else to do it.你可以自己做，也可以请人做。Seize the chance,otherwise(or else)youll regret it.抓住机会，否则你会后悔的。(otherwise,or else常接在祈使句后面)You can either stay

24、at home or go fishing.你可以待在家里，或是去钓鱼。He went rather than stay as an unwelcome guest.他走了，不愿留下来做个不受欢迎的客人。4表示因果关系的并列连词表示因果关系的并列连词有：so(所以)，for(因为)。It is morning,for the birds are singing.是早晨了，因为鸟叫了。It was late,so I went home.天色已晚，因此我就回家了。注意：then(那么，因而)，thus(因而),hence(因此)，therefore(因此，所以)等副词常可放于句首表示因果关系。H

25、e was busy,therefore he could not come.他很忙，因此不能来。He studied hard,thus he got a full mark.他很用功，因而得了满分。His car broke down,thus he was late for work.他的车坏了，因此他上班迟到。It is winter now,hence the days will be shorter.现在是冬天，因此白天会短些。(三)从属连词用来连接主句和从句的连词叫从属连词。从属连词可分为两类：引导名词性从句的从属连词和引导状语从句的从属连词。1引导名词性从句的从属连词引导名词性

26、从句的从属连词有连接词that,whether和if，这些连接词在句中不充当任何句子成分；连接代词主要有who,whom,whose,which,what等，它们在句中可作主语、宾语、定语等；连接副词主要有when,where,how,why等，它们在句中可作状语(详情见名词性从句)。We know(that)the earth goes round the sun.我们知道地球围绕太阳运转。(宾语从句)What we need is more time.我们需要的是更多的时间。(主语从句)Thats what I want.那就是我想要的。(表语从句)The news that our te

27、am had won was very exciting.我们队赢了，这消息十分令人振奋。(同位语从句)2引导状语从句的从属连词1)引导时间状语从句的从属连词when(当时),while(在期间),as(当时，一边一边),after(在之后),before(在之前),since(自从以来),till/until(直到，直到才),once(一 旦),as soon as(一 就),the moment/instant(一就),no sooner.than(刚就),hardly.when(刚就)等。Once you begin,you must go on.一旦你开了头，你就必须继续下去。When

28、 it rains,I go to school by bus.下雨时，我坐公共汽车去上学。2)引导原因状语从句的从属连词as(由于),because(因为),since(既然)等。He didnt go to school because he was ill.他因为生病没去上学。Since everybody is here,lets begin.既然大家都在这里，我们就开始吧。3)引导地点状语从句的从属连词where(在地方)，wherever(无论在哪里)等。Wherever she may be,she will be happy.她无论在什么地方都快乐。Where there is

29、 a will,there is a way.有志者，事竟成。4)引导条件状语从句的从属连词if(如果),unless(除非),so/as long as(只要)等。He will not come unless he is invited.除非被邀请，否则他是不会来的。Youll be late for the class if you dont hurry.如果你不快点，你就会上课迟到。5)引导目的状语从句的从属连词that(以便),so that(为了),in order that(为了),lest(以防，免得),in case(以防，免得)等。She took medicine on

30、time in order that she might get well soon.为了快点康复，她按时吃药。I came here that I might take a good look at the new bridge.我来这儿，为的是好好看看这座新桥。6)引导结果状语从句的从属连词so(结果),so that(结果),so.that/such.that(如此以致),that(以致)等。It was very cold,so that the water in the bowl froze.天气很冷，碗里的水都结冰了。He is such a good student that w

31、e all like him.他是个好学生，我们都喜欢他。7)引导让步状语从句的从属连词though/although(虽然),as(虽然),even if/even though(即使),however(无论怎样),whatever(无论什么),whoever(无论谁),no matter how/what/which/.(无论多么/什么/哪一个)等。Even if you were here yesterday,you couldnt help him.即使昨天你在这，你也帮不了他。Though he is old,he still works hard.虽然他老了，可是他还努力地工作。8

32、)引导方式状语从句的从属连词as(正如),as if/as though(好像，似乎)等。He speaks English as if he were an Englishman.他讲起英语来就像是英国人似的。Use a book as a bee does a flower.像蜜蜂利用花一样去利用书籍吧。9)引导比较状语从句的从属连词as(如),as.as.(像一样),not so.as.(与不一样),than(比)等。He works harder than before.他比以前更努力工作。His elder sister is as tall as his mother.他姐姐和他母

33、亲一样高。(四)部分连词的用法比较1when和while两个词都可以表示“当时”；引导时间状语从句。when引导的时间状语从句的谓语动词既可以是延续性的，也可以是终止性的；while引导的时间状语从句的谓语动词只能是延续性的。My brother came in when/while I had dinner.我弟弟进来时我在吃饭。The train had just started when we arrived at the station.我们刚到火车站火车就走了。He was doing his homework when I came in.(当)我进来时，他正在做家庭作业。I ca

34、me in when/while he was doing his homework.当他在做家庭作业时，我走了进来。While/When I was in the town,I saw him twice.(当)我在城里时，见过他两次。Strike while the iron is hot.趁热打铁。when还可译作“这时”，while还可译作“而”。He was playing football outside when it began to rain.他在外面踢足球，这时开始下起雨来。He is tall while his elder brother is short.他个子高，而

35、他哥哥个子矮。2because,since和asbecause引导的从句通常表示说话人认为听话人不知道的原因或理由，从句往往是整个主从复合句的重心。He was annoyed because he missed the bus.他感到为难是因为他没有赶上那班车。since和as表示原因时，往往表示人们显然已知道的理由或原因；因此，侧重点是主句的内容，原因只作附带说明。在语气上，because最强，since次之(在意义上相当于汉语中的“既然”)，as最弱。Since his method doesnt work,lets try yours.既然他的方法不起作用，我们就试一试你的。As sh

36、e was in a bad mood,we left her alone.由于她心情不好，我们不去打扰她了。He is absent from school because he is ill.因为他生病，所以他没来上课。Since everybody is here,lets begin.既然大家都到了，我们就开始吧。3if和unless引导条件状语从句的连词，主要是if和unless，由if引导的条件状语从句可以是真实条件句，也可以是非真实条件句。真实条件句所表示的条件指的是事实，即可以实现的事，非真实条件句指的是与事实相反或不大可能实现的事。If it rains,the match

37、will be cancelled(取消)如果天下雨，比赛将被取消。If I were you,I should consult(请看病)a doctor.我要是你，我就去看医生。If I had tried hard last term,I would have succeeded.如果上学期我努力的话，我现在已经成功了。unless在意义上相当于if.not。You will fail unless you work harder.除非你努力，否则你不会成功。Do not come unless I call you.我没叫你，你就不用来。4though和as两 个 词 都 可 表 示“虽

38、 然”；引 导 让 步 状 语 从 句。though引导的从句用正常语序；as引导的从句用倒装语序，即把从句中的表语、状语或动词原形放在as之前。Cold as it was,he went on working.Though it was cold,he went on working.尽管天气冷，可他仍继续工作。Child as he is,he knows a lot.Though he is a child,he knows a lot.虽然他是个孩子，可是他很懂事。Fast as you read,you cant finish the book in three days.Thou

39、gh you read fast,you cant finish the book in three days.尽管你读得快，你也不能三天内读完这本书。Try as he might,he couldnt get rid of the difficulty.Though he might try,he couldnt get rid of the difficulty.不管怎样努力，他还是摆脱不了困难。5if和whether1)表示“是否”时，两个词都能引导宾语从句。I wonder if/whether you can examine him now.不知你现在是否可以给他检查一下。注意：(

40、1)如果主句的谓语是短语动词，用whether，而不用if。Everything depends on whether we have enough money.一切都取决于我们是否有足够的钱。(2)某些动词(如discuss)后的宾语从句，用whether而不用if来引导。They discussed whether they should help her.他们商议他们该不该帮助她。(3)宾语从句移至句首时，用whether，而不用if。Whether it is true or not,I cant say.这是不是真的，我不敢说。(4)宾语从句为否定形式时，通常用if，而不用wheth

41、er。I asked her if he wouldnt come.我问她他是不是会来。2)if可译作“如果”，引导条件状语从句。If I were you,I would not go.如果我是你，我就不去。3)whether可译作“不管；无论”，引导让步状语从句。Whether he agrees or not,I shall do that.不管他同意与否我都要做这事。4)whether可以引导主语从句、表语从句、同位语从句，接不定式，或接or not等(if则不能)。Whether he will come or not is unknown.还不知道他来不来。(主语从句)The qu

42、estion is whether it is worth doing.问题是这件事是否值得去做。I have no idea whether he is there.我不知道他是否在那里。(同位语从句)I dont know whether he will do it or not.我不知道他是否会做这事。(接or not)She hasnt decided whether to go or not.她还没有决定去还是不去。(接不定式)6but和however，这两个词都作“但是”；“然而”解释，而且都可以引出并列分句。但从语义上看，but所表示的是非常明显的对比，转折的意味比however

43、强。从语法上看，but是一个并列连词，而however却是个连接副词。从语序上看，but总是位于它所引出的分句之首，而however却可位于分句之首、之中或之尾，但译成汉语时一定要放在分句之首。如：He said that it was so,he was mistaken,however.他说事情是这样，但是他错了。The situation looked desperate but they didnt give up hope.从现有的情况看似乎没有希望了，但他们没有放弃。Id like to go with you,however,my hands are full.我很想和你一块出去

44、，可是我忙不过来。She cut her knee badly,but didnt cry.她膝盖割破得很厉害，但她没有哭。On the question of style,however,I will make no concession.但是，关于风格问题，我决不会让步。I know it happened,but I cant bring it back to my mind.我知道有这么回事，但回忆不起来了。You can phone the doctor if you like.However,I very much doubt whether you will get him to

45、 come out on Saturday night.如果你愿意，你可以给医生打电话，但是我非常怀疑在这星期六的晚上你能否把他请出来。Her brother is the king,but she is the effective ruler.她兄弟是国王，但她却是真正的主宰者。7although是从属连词，引导让步状语从句，意为“虽然”；“尽管”。如：Although it was only four oclock,the lights were already on.虽然只有四点钟，电灯已经亮了。Although the car is old,it still runs well.虽然这

46、辆车旧了，但仍然很好用。Although she was ill,she worked hard.虽然她病了，但工作还是很努力。They are generous although they are poor.他们虽然穷，但是很大方。注：although也有“但是”；“然而”之意。如：He said they were married,although Im sure they arent.他说他们已经结婚了，不过我肯定他们没有。I can see his point,although,I have to say,I think he is wrong.我懂得他的意思，但是我得说，我认为他是错

47、的。I dont think it will work,although its worth a try.我虽然认为那不行，但值得一试。8while在本单元中是并列连词，表示转折。如：I like music while my brother likes sports.我喜欢音乐，而我哥哥喜欢体育。That region has plenty of natural resources while this one has none.那个地区有丰富的自然资源，而这个地区没有。注：while也有“虽然”；“尽管”之意，多放在句首。如：While I admit his good points I

48、can see his bad.虽然我承认他的优点，但我也看到了他的缺点。While I dont like that artist personally,I admire his works.就我个人而言，虽然我不喜欢这位艺术家，但我喜欢他的作品。While he admitted stealing the money,he denied doing any harm to the owner.虽然他承认偷了钱，可是他却否认对失主造成什么损害。高考直击(1)(2009全 国 卷)Charles was alone at home,with_looking after him.Asomeone

49、Banyone Cnot one Dno one解析：本题题意：查尔斯独自一人在家，没有人照看他。no one表示“没有人(谁也不)”。答案：D(2)(2009北 京)You may use the room as you like_you clean it up afterwards.Aso far as Bso long asCin case Deven if解析：本题题意：你可以随便使用这个房间，只要你用过后把它打扫干净就行了。so/as long as表示“只要”，引导条件状语从句。例如：It matters little who does it so long as it is do

50、ne.只要事情做了，谁做都行。注意：as you like表示“随你的便”；例如：Stay as long as you like.你愿停留多久皆可。答案：B(3)(2009陕 西)My parents dont mind what job I do_I am happy.A.even though B.as soon asC.as long as D.as though解析：考查状语从句。根据题干意思可知此处是条件状语从句，引导词意为“只要”；故选C。even though引导让步状语从句，意为“即使”；as soon as引导时间状语从句，意为“一就”；as though引导方式状语从句，

51、意思为“仿佛；好象”。答案：C(4)(2009山东)Shall we have our picnic tomorrow?_it doesnt rain.AUntil BWhileCOnce DIf解析：本题考查交际用语，意思是：如果明天不下雨的话。答案：D(5)(2010安徽29)The engineers are so busy that they have zero time for outdoor sports activities，_they have the interest.A.wherever B.wheneverC.even if D.as if解析：本题考查状语从句连词辨析。

52、句意为“工程师们非常繁忙，即使(even if)有户外体育活动的兴趣也没有时间去做。”答案：C(6)(2010安徽33)Just use this room for the time being,and well offer you a larger one _ it becomes available.A.as soon as B.unlessC.as far as D.until解析：本题考查状语从句连词辨析。句意为“仅暂时使用此房间，它一(as soon as)可以正常使用，我们就提供你一个大点的。”答案：A(7)(2010北京30)_ they decide which college

53、 to go to,students should research the admission procedures.A.As B.WhileC.Until D.Once解析：本题考查连词。此题重在句意的判断。“一旦学生们决定了去哪所大学读书，他们就得研究下办理入学的手续。”A.As当；因为.B.while做连词强调一件事发生时另外一个动作正在进行；C.Until直到.D.Once一旦。因此选D。答案：D(8)(2010江西22)Our holiday cost a lot of money.Did it?Well,that doesnt matter_ you enjoyed yourse

54、lves.A.as long as B.unlessC.as soon as D.though解析：考察连词和具有连词作用的词组。as long as“只要”；unless“除非，否则”；as soon as“一就”；though“虽然”，后一句为“只要你玩的开心，花多少钱就不重要。”答案：A即学即用Excuse me for breaking in,_I have some news for you.Aso BandCbut Dyet答案：C_I accept that he is not perfect,I do actually like the person.AWhile BSince

55、CBefore DUnless答案：AWe managed to arrive at the place_the car had broken down on the way.Awhether BifCunless Dthough答案：DDont be afraid of asking for help_it is needed.Aunless BsinceCalthough Dwhen答案：DWere going to the bookstore in Johns car.You can come with us_you can meet us there later.Abut BandCo

56、r Dthen答案：CJohn shut everybody out of the kitchen_hecould prepare his grand surprise for the party.Awhich BwhenCso that Das if答案：CThe film brought the hours back to me_Iwas taken good care of in that faraway village.Auntil BthatCwhen Dwhere答案：CSomeone called me up in the middle of the night,but they hung up_I could answer the phone.Aas BsinceCuntil Dbefore答案：DDid you remember to give Mary the money you owed her?Yes.I gave it to her_I saw her.Awhile Bthe momentCsuddenly Donce答案：BAfter the war,a new school building was put up_there had once been a theatre.Athat BwhereCwhich Dwhen答案：B