一位优秀的教师不打无准备之仗，会提前做好准备，高中教师要准备好教案，这是每个高中教师都不可缺少的。教案可以让学生们充分体会到学习的快乐，帮助高中教师提高自己的教学质量。优秀有创意的高中教案要怎样写呢？下面是小编精心收集整理，为您带来的《Unit4　HesaidIwashard-working知识归纳》，希望能对您有所帮助，请收藏。

Unit4　HesaidIwashard-working知识归纳

1．单词与短语
ever　madanymoresnack
messagesuppose　hard-working　nervous
semesterworst　true　disappointing
lucky　copyhers　decision　
start　influence　peace　border
danger
firstofall首先
passon　传递
besupposedto　被期望或被要求......
dobetterin　在......方面做得更好
beingoodhealth身体健康
reportcard　成绩单
getover　克服；恢复；原谅
openup　打开
carefor　照料；照顾
haveapartyforsb.　为某人举行一次聚会
bemadatsb

2．目标句型：
转述他人话语
Whatdidsb.say?
HesaidI…
Shesaidshe…
Theysaid…

3．语法
直接引语和间接引语

直接引语和间接引语
（一）直接引述别人的原话，叫做直接引语；用自己话转述别人的话，叫做间接引语。间接引语一般构成宾语从句。直接引语必须放在引号内，间接引语则不用引号。直接引语改为间接引语时，除将引语部分变成宾语从句外，还必须对直接引语中的人称、时态、指示代词、时间状语、地点状语等进行改变。

1.时态的变化：直接引语变为间接引语时，通常受转述动词said，asked等的影响而使用过去化的时态，即把原来的时态向过去推，也就是一般现在时变为一般过去时，现在进行时变为过去进行时等。

　例如：
　Tomsaidtome,“Mybrotherisdoinghishomework.”
　→Tomsaidtomethathisbrotherwasdoinghishomework.

2.人称代词、指示代词、时间状语、地点状语等等的变化；根据意义进行相应的变化。

　例如：
　SheaskedJack,“Wherehaveyoubeen?”
　→SheaskedJackwherehehadbeen.

　Hesaid,“Thesebooksaremine.”
　→Hesaidthatthosebookswerehis.

（二）直接引语改为间接引语时，都使用陈述语序，但是因为原句的句式不同，所以变成间接引语时所用的连词会有所不同。

1.陈述句的间接引语
陈述句由直接引语变间接引语，通常由that引导，可以省略。

　“Iwanttheblueone.”hetoldus.“我想要兰色的。”他说。

　→Hetoldusthathewantedtheblueone.他说他想要兰色的。

　Shesaidtome,“Youcan’tsettleanythingnow.”她对我说：“此刻你无法解决任何事情。”

　→ShetoldmethatIcouldn’tsettleanythingthen.　她对我说那时侯我无法解决任何事。

2.疑问句的间接引语
直接引语如果是疑问句，变成间接引语后，叫做间接疑问句。间接疑问句为陈述语序，句末用句号，动词时态等的变化与间接陈述句相同。引述动词常用ask,wonder,wanttoknow,inquire。间接疑问句一般有三种：

(1)．一般疑问句由直接引语变为间接引语时，由whether或if引导。

如：
　“HasheeverworkedinShanghai?”Jimasked.
“他在上海工作过吗？”吉姆问。

　→Jimaskedwhether/ifhehadeverworkedinShanghai.
吉姆问他是否在上海工作过。

　“Canyoutellmethewaytothehospital?”Theoldmanasked.
那个老人问：“你能告诉我去医院的路吗？

　→TheoldmanaskedwhetherIcouldtellhimthewaytothehospital.
那个老人问我是否能告诉他去医院的路。

(2).特殊疑问句由直接引语变为间接引语时，仍由原来的疑问词引导。

如：
　“Whichroomdoyoulivein?”Heasked.“你住哪个房间？”他问我。

　→HeaskedmewhichroomIlivedin.他问我住哪个房间。

　“Whatdoyouthinkofthefilm?”Sheasked.她问“你怎么看这部电影？”

　→Sheaskedherfriendwhatshethoughtofthefilm.　她问她的朋友怎么看这部电影。

(3).选择疑问句由直接引语变为间接引语时，由whether/if…or引导。

如：
　“IsityourbikeorTom’s?Mumasked.
妈妈问：“这是你的自行车还是汤姆的？”

　→Mumaskedwhether/ifitwasmybikeorTom’s.
妈妈问这是我的自行车还是汤姆的。

　“Doesyoursisterlikebluedressesorgreenones?”Kateasked.
“你妹妹喜欢兰色的裙子还是绿色的？”凯特问。

　→Kateaskedwhether/ifmysisterlikedbluedressesorgreenones.
凯特问我的妹妹喜欢兰色的裙子还是绿色的。

3.祈使句的间接引语
当祈使句变为间接引语时，间接祈使句的引述动词常用tell，ask，order，beg，request，order等，而把直接祈使句变成带to的不定式短语。

如：
Jacksaid,“Pleasecometomyhousetomorrow,Mary.　”杰克说：“玛丽，明天请到我家来。”
→JackaskedMarytogotohishousethenextday.杰克请玛丽第二天到他家去。

Theteachersaidtothestudents,”Stoptalking.”老师对学生们说：“不要讲话了。”
→Theteachertoldthestudentstostoptalking.老师让学生们不要说话了。

“Don’ttouchanything.”Hesaid.“不要碰任何东西。”他说。
→Hetoldusnottotouchanything.他对我们说不要碰任何东西。

4.动词时态和代词等的变动
(1).某些代词，限定词，表示时间或地点的副词和个别动词在间接引语中的变化规则如下：
　直接引语间接引语
　today　thatday
　nowthen,atthatmoment
　yesterday　thedaybefore
　thedaybeforeyesterday　twodaysbefore
　tomorrow　thenextday/thefollowingday
　thedayaftertomorrow　twodaysafter,/intwodays
　nextweek/monthetc　thenextweek/monthetc
　lastweek/monthetc　theweek/monthetc.before
　here　there
　this　that
　these　those
　come　go
　bring　take

(2).如果引述动词为现在时形式，则间接引语中的动词时态，代词，限定词和表示时间或地点的副词不用变化。而如果引述动词是过去时，以上内容就要有相应变化。变化情况如下：

　现在时间推移到过去的时间，即一般现在时变为一般过去时；

　“Ifeelbettertoday.”Hesaid.
“我今天感觉好多了。”他说。
　→Hesaidthathefeltbetterthatday.
他说他那天感觉好多了。

　现在进行时变为过去进行时；

　“XiaoMingisdoingsomewashing”Mumsaid.
“小明正在洗衣服。”妈妈说。
　→MumsaidthatXiaoMingwasdoingsomewashing.
妈妈说小明正在洗衣服。

练习
I.Putthefollowingintoreportedspeech.
1.“Inmostcountriesredstandsfordanger.”SaidMr.Jackson.

2.“Youmustleaveamessageforyourmother.”SaidTom.

3.“Areyoubeingattendedto,sir?”Heasked.

4.“ShallIcarryyourbagforyou?”Maryasked.

5.“Doyouknowhername?”MyfriendJackaskedme.

6.“Whereisthenearesthospital?”Johnasked.

7.“Dontlookoutofthewindowwhenyouhaveclasses.”Ourteachertoldus.

8.“Makegooduseofyourtime.”Mr.Liadvised.

9.HeaskedLiYing“WereyouwatchingTVatthistimeyesterday?”

10.Heaskedme,“Whendidyouseethefilm?”

II.Pleasechangethefollowingsentencesfromindirectspeechintodirectspeech.
11.BettyaskedmeifIhadbeenathomethedaybefore.
Bettyaskedme，“______athome___?”

12.Shesaidthatshehadbeenbackforaweek.
Shesaid，“_________foraweek.”

13.Mr.SmithsaidthatJohnhadtoldhimallaboutitthreeweeksbefore.
Mr.Smithsaid，“John______allaboutitthreeweeks___.”

14.Theteacheraskedhisstudentwhyshehadmadesomanymistakesinthetestthattime.
Theteacheraskedhisstudent，“Why______somanymistakesinthetest__time?”

　15.Theteacheraskeduswhetherwewereready.
　Theteacheraskedus，“_________?”

　16.Theteachertoldhernottobelateanymore.
　Theteacher______her，“______lateanymore!”

　17.Mydoctortoldmenottoreadinbed.
　Mydoctor______me，“______inbed.”

　18.LiuYingtoldmethatshewouldhelpmewithmyEnglish.
　LiuYingsaidtome，“______help___with___English.”

　19.Doyouknowwhatfactoryhisfatherworksin?
　Whatfactory___hisfather___in?Doyouknow?

　20.Themonitortoldusthatweweregoingtohaveameetingthenextday.
　Themonitorsaid,“We______tohaveameeting___.”

III.Reading
Manhasalwayswantedtofly.Someofthegreatestmeninhistoryhavethoughtabouttheproblem.Oneofthese,forexample,wasthegreatItalianartist,LeonardodaVinci.Inthesixteenthcenturyhemadedesignsformachinesthatwouldfly.Amongthesedesignstherewasactuallyoneforahelicopter.Therewasalsoanotheroneforaparachute(降落伞).Butthesethingswerealldesigns.Theywereneverbuilt.

Throughouthistory,otherlessfamousmenhavewantedtofly.AtypicalexamplewsamaninEngland800yearsago.Hemadeapairofwingsfromchickenfeathers.Thenhefixedthemtohisshouldersandjumpedintotheairfromatallbuilding.Hedidnotflyveryfar.Instead,hefelltothegroundandbrokeeveryboneinhisbody,

ThefirstrealstepstookplaceinFrance,in1783.Twobrothers,theMontgolfiers,madeaverylarge"hotairballoon".Theyknewthathotairrises.Whynotfillaballoonwithit?Theballoonwasmadeofclothandpaper.InSeptemberofthatyear,theKingandQueenofFrancecametoseetheballoon.Theywatcheditcarrytheveryfirstairpassengersintothesky.Thepassengerswereasheep,achickenandaduck.Wedonotknowhowtheyfeltaboutthetrip.Butwedoknowthatthetriplastedeightminutesandthattheanimalslandedsafely.Twomonthslater,twomendidthesamething.On21November,PilatredeRozierandtheMarquisaArlanderoseaboveParisinasimilarballoon.Theirtriplastedtwenty-fiveminutesandtheytraveledabouteightkilometers.

21.Inthesixteenthcentury,__________wasbuilttohelpflyinthesky.
A.ahelicopter
B.parachute
C.designsformachines
D.nothing

22.Themanwithapairofwingsfromchickenfeathers_________.
A.flewveryfar　
B.flewashortdistance
C.realizedhisdream
D.felltothegroundanddied

23.The“hotairballoon”couldflybecause__________.
A.hotairrises
B.itismadeofclothandpaper
C.theresaballoonwithit　
D.itsverylarge

24.On21November,PilatredeRozierandtheMarquisaArlanderoseaboveParis_______.
A.inthesameballoonasasheep，achickenandaduckwereoncein
B.inacompletelydifferentballoon
C.inanother“hotairballoon”
D.inahelicopter

25.Thebesttitleforthispassageis“_____________”.
A.TwoBrothers，TheMontgolgiers
B.HotAirBalloonsAndWingsMadeFromChickenFeathers
C.DesignsForMachinesThatWouldFly
D.TripInHotAirBalloon

Key
I.
1.MrJacksonsaidthatinmostcountriesredstoodfordanger.

2.TomsaidthatImustleaveamessageformymother.

3.Heaskedif/whetherIwasbeingattendedto.

4.Maryaskedmewhether/ifIshouldcarryherbagforher.

5.MyfriendJackaskedmeifIknewhername.

6.Johnaskedmewherethenearesthospitalwas.

7.Ourteachertoldusnottolookoutofthewindowwhenwehaveclasses.

8.Mr.Liadvisedustomakegooduseofourtime.

9.HeaskedLiYingifshewaswatchingTVatthattimeyesterday.

10.HeaskedmewhenIsawthefilm.此句涉及到某一具体时间，不必转换成过去完成时。

II.
11.Wereyou,yesterday

12.Ivebeenback

13.toldme,ago

14.didyoumake/haveyoumade

15.Areyouready?

16.saidto,Dontbe

17.saidto,Dontread

18.Iwill,you,your

19.does,work

20.aregoing,tomorrow

III.
21-25DDACB

相关知识

Unit4HesaidIwashard-working.SectionA

作为优秀的教学工作者，在教学时能够胸有成竹，教师要准备好教案为之后的教学做准备。教案可以让学生们能够更好的找到学习的乐趣，帮助教师有计划有步骤有质量的完成教学任务。那么，你知道教案要怎么写呢？下面是小编为大家整理的“Unit4HesaidIwashard-working.SectionA”，欢迎您参考，希望对您有所助益！

Unit4HesaidIwashard-working.SectionA
一、教学内容
学习如何转述他人话语，即直接引语与间接引语的转换。
二、教学目标
1．语言结构
（1）直接引语与间接引语
（2）一般过去时及过去进行时
（3）情态动词can表能力
2．语言目标
（1）重点词汇：ever,mad,anymore,snack,directspeechreportedspeech.
（2）重点句子：
Whatdidshesay？
ShesaidshewashavingapartyforLana.
Shesaidshecouldspeakthreelanguages.
3．能力目标
（1）自我评价能力
（2）人际交往能力
（3）语言综合运用能力
三、教学重点难点
重点：如何转述他人话语
难点：直接引语与间接引语的转换
四、设计理念
以日常会话导入新课，利用活泼的多媒体画面，调动学生积极性，并穿插进行口语及听力练习，锻炼学生的听说能力。
听说材料采取先提出问题，带着问题听、理解的形式，注意了整体教学，整体理解；然后采取互相对话的形式练习、巩固。词汇和短语在语境中自然接触，很容易让学生领会。教学活动由易到难，设计任务型学习活动，在真实任务中引导学生主动思考，培养学生的创造性思维能力和交际能力。在日常教学中做到理论联系实际,学以致用，体会真实环境下的语言运用。
五、教学过程
Step1Revision
Askseveralstudentsquestionslike:
T:Whatareyougoingtodoafterschool?
S1:I’mgoingtodomyhomework.
T:OK.Andwhatareyougoingtodo?
S2I’mgoingtoplayfootball.
ThenwritethewordsHesaidandshesaidontheblackboard.Letthestudentstalkaboutwhattheyaregoingtodoafterschool.Practiselikethis:
Shesaidshewasgoingtodoherhomework.
Hesaidhewasgoingtodohishomework.
Step2Presentation
Tellthestudents:InthisUnitstudentslearntoreportwhatsomeonesaid.Payattentiontohwtochangeit.
Page26.1a.Askandanswerquestionsaboutwhatthepeopleinthesoapoperasaidlikethis:
A:Whatdidshesay?
B:ShesaidshewashavingasurprisepartyforLanaonFridaynight.
Step3Practice
LookatthepicturesOnPage26.Askandanswerinpairs,thencheckthem.
Step4Listening
Page26.1b.Listenandnumberthestatements[1-4]inthepicture.Thenchecktheanswers.
Page27.2aFirstaskdifferentstudentstoreadthesentencestotheclass,thenlistenandcircletrueorfalseforeachstatement.
Page27.2bListenagain.WhatdidthepeopleonTVsay?Circlethecorrectanswers.
Step5Practice
Page27.2cThisactivityprovidesguidedoralpracticeusingthetargetlanguage.Firstreadtheinstructionstotheclass.Usethewordsandpicturesinactivity2bandmakeconversationsinpairs,thencheckdifferentpairs.
Step6Summarize
Lookatthegrammarfocusandsummarizedirectspeechandreportedspeech.Tellthestudents:Whenyoureportwhatsomeonesaid,youusewordsthattalkaboutthepast.Somerules:
DirectSpeechReportedSpeech
1.am/is1.was
2.are2.were
3.have/has3.had
4.will4.would
5.can5.could
6.may6.might
Step7Exercise
Page28.3aReadthenewspaperstoryandfillintheblanks,thenchecktheanswers.
Page28.3a4Letthestudentspracticespeakingandlisteningskillsinroleplays.Ingroupsoffour,completetheroleplays,thenaskseveralstudentstopresenttheirroleplaystotheclass.Askthestudentstovoteonthebestroleplay.
Step8Homework
Page28.3bWritingpractice.Imagineandfinishthenewspaperarticle.

教案点评：本教学设计适应新教材课程改革要求，最大程度地做到了教师指导下的学生积极参与，使学生有充分的活动和表达自由，在学习过程中不断地锻炼自己、完善自己，培养学生的英语思维能力。教师充分利用了各种活动进行教学，使学生在真实情景中进行语言练习，更好地培养了学生的综合语言运用能力及英语学习兴趣。如果在教学中多一些激励机智，更及时地给予评价及反馈，活动的效果会更好，学生的参与热情及学习积极性会更高。

高二英语unit4重要词汇归纳

高二英语unit4重要词汇归纳

Unit4
dailyn日报
adj每日的；日常的
rosen玫瑰花
journalistn记者；新闻工作者
editorn编辑
advertisementn登广告；广告
headlinen（报刊的）大字标题
checkvt检查；核对
interviewnvt采访
magazinen杂志
chiefadj主要的；首要的
eventn事件；大事
getdownto开始认真（做某事）
fixvt确定；决定
face-to-face面对面的；当面的
photographern摄影师
immediatelyadv立即
takeaphotograph照一张（....的）相
developvt冲洗（照片）
handvt给；传递
addvt添加；增加
delivervt投递（信件、邮包等）
lorryn（英）运货汽车；卡车
railn铁路
speedn速度
vivt(使）加速
latestadj最近的；最新的
publishvt出版；发行
editionn版；版本
weeklyadj每周的
BusinessWeekly每周商刊
sectionn段；部分；部门
bepopularwithsomebody受某人欢迎
aswell也；又
besidesadv还有；此外
prep除……以外
suitableadj合适的；适宜的
rewritevt重写
carefor喜欢；想要

Unit4　Sharing

Unit4　Sharing
教材分析　
本单元的话题是Sharing，主要涉及帮助弱者、志愿服务、合作分享等。通过听、说、读、写等各种活动学习相关的语言知识，使学生了解世界上很多地方依然很落后，从而懂得同情，学会分享。了解一些志愿者工作的信息，培养学生互助合作的精神和社会责任感。结合针对短文话题的探讨激发学生的国际意识，通过各种渠道力所能及地为贫困地区的孩子作出自己的贡献。
WarmingUp部分是一个调查，分成三项任务：首先回顾自己曾经做过的助人为乐的好事，并采访三位同学；然后，根据调查内容列举班级同学所做的好事；最后讨论volunteer的内涵。通过这些任务，让学生懂得什么是“帮助”，反思自己是否乐于助人，以及怎样做才是“志愿者”，由此为后面的短文学习做好铺垫。
Pre－reading是Reading的热身活动。交代了阅读文章的文体(letter)和作者(ayoungAustralianwoman，Jo)，还根据她在PNG拍的10张照片提出了5个问题，回答这些问题有助于学生加深理解“志愿者活动”的意义。
Reading是一篇Jo写给Rosemary的信。其中介绍Jo在PNG(PapuaNewGuinea)的一个小山村教书。在她写给Rosemary的信中，作者描述了该村学校的情况和去一个学生家做客的经历，使学生感受到PNG的儿童生活处境的艰难，更加珍惜自己的学习机会。
Comprehending是根据短文设计的阅读理解试题。第一个练习要求学生读懂书信的内容，用表格的形式帮助学生整理书信中提到的关于巴布亚新几内亚村落生活及风俗习惯的信息，属于细节题。第二个练习要求学生对文中提到的五个现象进行分析，说明原因，属于细节推理题。第三个练习要求学生通过阅读分析生活在小山村中的积极面和消极面，这个练习进一步地开阔学生的思维，使学生对艰苦的生活有更深的理解。第四个练习要求学生小组活动，讨论四个问题，进一步巩固学生对于课文内容的理解，并且让学生联系自己的实际情况，通过比较校舍、教学条件、生活状况等方面的问题，引发学生的深层思考，谈谈自己是否愿意参加志愿者活动。第三、四两个练习都属于深层思考的问题。
LearningaboutLanguage分词汇和语法两部分。其中，第一部分是有关此篇短文中的重点单词和短语。设置了三个练习，一是根据所给解释从所学词汇中选择相应的单词；二是用恰当的词汇完成一篇短文；三是根据解释组成词组，并用词组编对话。第二部分是有关限制性定语从句的复习。首先从课文中找出含有限制性定语从句的句子；然后用定语从句完成句子，对定语从句加以运用；再用含有定语从句的句子回答问题；最后是两人结对活动，进一步练习使用定语从句。
UsingLanguage是对Reading的延伸。通过阅读，参与“Giveanunusualgift”的活动。这个部分由三个部分组成，综合训练学生听说读写四个方面的能力。“读与说”通过图文结合的方式，介绍了一些特殊的礼品——为穷人和真正需要它们的人选购礼品。阅读之后，完成两个练习：回答问题和把礼物名称和详细介绍配对。“听与说”部分是采访默里大夫的经历，以听力训练为核心设置了四个活动。1.讲述一个人的生平，用到了时间表达法；2.通过列表把握听力中的细节；3.在涉及听力内容之前让学生先就有关听力中的话题进行讨论，有助于学生快速并准确地把握听力内容；4.展开讨论，让学生思考自己将来是否愿意像默里大夫那样做个志愿服务工作者。“写作”根据“听与说”中的话题，运用时间表达方式，根据给出的6个方面对默里大夫的情况进行写作。
课时划分　
在对本单元的各部分材料进行分析、整合后，确定了以下六个重点课时：
课时一：WarmingUpandListening(听力课)
从话题内容和训练目的来看，WarmingUp与UsingLanguage中的Listeningandspeaking比较接近，所以将WarmingUp与Listeningandspeaking的第1、2、3题和Workbook中的Listening以及ListeningTask整合在一起，设计成任务型“听力课”，以训练听前预测的能力和学习用时间表达方式来介绍一个人的生平经历的方法。
课时二：Speaking(口语课)
将上一节听力课剩下的部分Listeningandspeaking中的第4题和Workbook中与上节课听力内容相关的Talking以及SpeakingTask整合在一起，设计成“口语课”，训练学生用英语表达自己的观点，并且说明这样做的理由。
课时三：Pre－readingandReading(阅读课)
这篇课文是一个志愿者的一封家书，她在巴布亚新几内亚共和国的一个小山村教书。信中详细地描述了她所在学校的情况和她去一个学生家做客的经历。通过这封信，学生可以了解巴布亚新几内亚共和国各部落的生活状况和风俗习惯，同时能够更好地理解志愿者的工作。
课时四：Grammar(语法复习课)
本单元的语法重点是复习限制性定语从句(RestrictiveAttributiveClause)。学生已经学过这个语法点，所以在这节课中，首先对限制性定语从句的特征、关系词做一个简要回顾，然后通过多种形式的练习，如填写关系词、造句和翻译等，使学生逐步掌握限制性定语从句的用法。这些教学环节，如开始部分的听句子、猜同学的游戏和结束部分的翻译或写作练习，都充分体现了在语境中学习语法、在语境中运用语法的教学原则。
课时五：Reading，SpeakingandWritingTask(综合运用课)
这节语言综合运用课把本单元的第二篇文章和课后练习中的写作练习组合到一起。一方面是由于这篇文章——“世界上最有用的礼物清单”，内容比较简单，不需要用一整节课来完成；另一方面是课后练习的写作任务——给一个被自己资助的孩子写封信，既切合本单元帮助他人的主题，题目中又已经列出了书信的结构，书信的内容也是介绍自己的学习生活，能够与学生的实际结合起来，学生写起来有话可说。
课时六：SummingUpandLearningTip(总结复习课)
复习课分成四个板块，板块一是复习课文内容和重要的词组句型。复习课文内容可以通过根据关键词组复述课文、回答问题和学生互批作文(用100词左右写一篇介绍部落生活和风俗的文章)等活动来完成。这篇作文是阅读课的家庭作业，放在此处，既检查了作业，又有助于课文的复习。板块二是复习语言知识，主要是用翻译、填词以及句型转换来复习。板块三是总结和概括语法项目。指导学生完成表格填充、知识树，使学生在脑海中对限制性定语从句形成一个完整的概念。板块四是总结。讨论分享的意义，让学生对于本单元的主题有更加清晰完整的认识，并且由生活中的分享谈到学习上的互相合作与分享，即LearningTip的内容。

学情分析　
1．学生经过高中阶段必修1～选修6的学习，具备了一定的阅读技能，如查找细节信息，猜测词义，抓住段落要点和全文大意等，在阅读速度方面也有了较大的提高，这有助于学生较好地完成这个单元的课文阅读。同时，在听、说、写等方面也有了一定的基础。
2．这个单元的话题是分享、帮助与合作。对于高二的学生而言，他们的价值观人生观已经基本形成，要想通过一个单元的学习，完全改变学生的价值观，难度比较大，但教师可以通过本单元安排的内容，如阅读志愿者的家书，了解一些捐助机构的工作，帮助学生认识这个世界，理解互助合作的意义，即在帮助他人的过程中实现自己的人生价值。
3．学生在这个单元的学习过程中需要用到预习策略、搜集分析信息策略、归纳整理策略及高效复习策略等。
Period1　WarmingUpandListening
教学目标　
1．语言知识目标
a．认识以下单词和短语：
volunteer，clinic，challenging，overthelastfewyears，inthefuture，intwoweekstime，acoupleof，developingcountry，MedecinsSansFrontieres(MSF)，Malawi，Sudan，TheFredHollowsFoundation，TheCancerCouncil，YouthintheCity，goblind，belief
b．注意以下几个重要句型：
WhydidMarydecidetoworkinadevelopingcountry?
IntheSudan，whywasitnearlyimpossibleforMarytogettotheclinicswhentherainscame?
WhywereconditionsintheclinicsintheSudanchallenging?
2．语言技能目标
通过听一段采访，了解默里大夫作为一个志愿者为MedecinsSansFrontieres(MSF)工作的经历，提高学生听前预测、注意细节信息等听力方面的技能。
3．语言能力目标
提高学生注意细节信息的听力能力，同时理解听力材料中出现的一些重要的词汇和表达方式。
4．情感态度与文化意识目标
借助听力材料，让学生思考自己将来是否愿意像默里大夫那样做志愿服务工作。把学生的生活实际和所听到的内容结合起来，能够培养学生正确的价值观。
重点难点　
1．教学重点：
a．学会边听边注意听力材料中的细节信息，并做笔记。
b．在讲述个人生平时，常采用时间表达法。学会关注对话中的时间表达法以及出现的先后次序。
2．教学难点：
a．根据列表掌握听力中的细节信息。
b．学习采用时间表达法来表述一个人的生平。
教学方法　
听力教学与合作学习
教学过程　
?Step1　Lead－in
1．T：Haveyoueverhelpedothers？Whatdidyoudotohelpyourparents？Orotherrelatives？Oryourfriends？Orpeopleinyourcommunity？Orpeopleoutsideyourcommunity？Imsureyouhavealottosay.OK，fourstudentsagroupandfinishthefollowingsurveyform.
Whatdoyoudotohelp...Name：Name：Name：
1.yourparents？
2.otherrelatives？
3.yourfriends？
4.peopleinyourcommunity？
5.peopleoutsideyourcommunity？
Suggestedanswers：
Whatdoyoudotohelp...Name：TomName：HelenName：Mary
1.yourparents？Cleanthefloor.Washdishes.Preparesupper.
2.otherrelatives？LendmybooksandCDstothem.Takecareofmycousinwhilehisparentsareaway.Comfortthemwhentheyaresad.
3.yourfriends？Repairtheircomputers.Helpthemwiththelessons.Doshoppingwiththem.
4.peopleinyourcommunity？Beacoachofthefootballlovers.Singanddancefortheelders.Helpmyneighbourscarrythingshome.
5.peopleoutsideyourcommunity？Planttrees.Helppeoplewithdisabilities.Returnthewallettotheowner.
2.Makeaclasslistofthedifferentthingsyourclassmatesdoforeachofthegroupsonthesurveyform.
3．Discusswhethersomeonewhohelpsthegroupsonthesurveyformcanbecalleda“volunteer”．
T：Whichonecanbecalledavolunteer？Orwhatkindofthingsdovolunteersdo?
Onlythosewhoworknotforrewards—especiallymoneyandmaterials，andarenotforcedtodosoarevolunteers.Andnotonlythepersonbutalsothesocietyandtheenvironmentbenefitfromit.Forexample，DrMaryMurraywasavolunteerworkingforMedecinsSansFrontieres(MSF)．
?Step2　Pre－listening
NowturntoPage35，readExercises1and2inListeningandspeaking，andpredictwhatyouwillhearinthelisteningmaterial.Youcanalsodiscusswithyourpartner.
S1：NowJenniferWellsisinterviewingDrMaryMurrayaboutwhathashappenedinMaryslife.
S2：SheonceworkedinaclinicinMalawiandSudan.
S3：MalawiandSudanaredevelopingcountries.
S4：ManychildrendiedwhensheworkedinMalawi.
S5：ConditionsintheclinicsintheSudanwereveryterribleandchallenging.
S6：MedecinsSansFrontieres(MSF)isanorganizationthatprovidesfreemedicalcaretochildreninpoorcountries.
T：Yousee，beforelisteningtotheinterview，youcangetmuchinformation，ifyoustudythequestionscarefully.Nowletslistentotheinterview.PleasepayattentiontothetimeexpressionsbecausetheyusetimeexpressionstotalkaboutMaryslife.Andthennumberthemintheorderyouhearthem.
______inthefuture______duringthe1980s
______foracoupleofmonths______overthelastfewyears
______forafurthersixmonths______intwoweekstime
?Step3　Listening
1．(Theteacherplaysthetapeandthestudentslistentoit.)
T：NowletschecktheanswersofExercise1.
Keys：__4__inthefuture__1__duringthe1980s
__2__foracoupleofmonths__3__overthelastfewyears
__6__forafurthersixmonths__5__intwoweekstime
2．T：Listenagain.Whenyouarelistening，youcanmakenotesofMarysexperiencesinthetablebelow.Andshareyournoteswithyourpartnerandthenwithothergroups.
TimePlaceEvent
The1980s
1992
1997
2001
Now
Future
Suggestedanswers：
TimePlaceEvent
The1980sSydneyStudiedmedicine.GottoknowtwoAfricanstudents.
1992AfricaVisitedhertwoAfricanfriendsandtheirfamilies.Workedintheirlocalhealthclinicforacoupleofmonths.
1997MalawiVolunteeredwithMSF.WorkedwithchildrenaffectedbyHIV/AIDS.
2001theSudanConditionswereverychallengingbecauseoftheheat，therains，thebasicconditionsintheclinics.
NowAustraliaHasreturnedfortwoweeks.
FutureWillreturntotheSudanforsixmoremonths.Afterthat，willprobablyreturntoAfricaagain.
3.T：Withapartneranswerthequestionsbeforeyoulistenforathirdtime.Asyoulistencheckyouranswers.
(1)WhydidMarydecidetoworkinadevelopingcountry?
(2)WhenMaryworkedinaclinicinMalawi，whydidthechildrendie?
(3)IntheSudan，whywasitnearlyimpossibleforMarytogettotheclinicswhentherainscame?
(4)WhywereconditionsintheclinicsintheSudanchallenging?
(5)WhydoesMaryenjoyherjob?
Suggestedanswers：(1)BecausewhensheworkedinanAfricanhealthclinic，shesawchildrenwithillnessesthatcouldbeprevented.
(2)Becausetheclinicsdidnthaveenoughmedicines.
(3)Becausetheroadsbecamesomuddythattheyspentmostoftheirtimediggingthecarout.
(4)Becauseitcouldbeveryhot；itcouldbenearlyimpossibletogettotheclinicswhenitrained；theclinicswereverybasicandtheonlytoolsshehadwereastethoscopeandherhands.
(5)Shefeelssheishelpingpeoplewhootherwisemaynotgethelp.
?Step4　ListeningonPage70
T：Perhapsyoumaywonderwhatwecandotoservecommunitiesoutsidetheschool？OK，doListeningintheWorkbookonPage70.
Firstpredictwhatyouwillhear，accordingtothepictureandExercise1.
1．Listentotheirdiscussionandnumbertheitemsbelowintheorderthatyoufirsthearthem.
______TheCancerCouncil(委员会)______oldpeople
______theenvironment______YouthintheCity
______PlanInternational______childreninhospital
______servingsouptothehomeless______TheFredHollowsFoundation
Keys：
__3__TheCancerCouncil(委员会)__6__oldpeople
__8__theenvironment__4__YouthintheCity
__1__PlanInternational__7__childreninhospital
__5__servingsouptothehomeless__2__TheFredHollowsFoundation
2．Listenagainandcompletethetable.
OrganizationWhosuggestedit？Whatdoesitdo？
1.PlanInternationalJason　Mick　Annie
2.TheFredHollowsFoundationJason　Mick　Annie
3.TheCancerCouncilJason　Mick　Annie
4.YouthintheCityJason　Mick　Annie
Keys：
OrganizationWhosuggestedit？Whatdoesitdo？
1.PlanInternationalMickSponorschildrenfrompoorcountries.
2.TheFredHollowsFoundationAnnieHelpsblindpeoplegettheirsightback.
3.TheCancerCouncilJasonDoesresearchintocancer.
4.YouthintheCityMickSupportsyoungpeoplefinanciallytostayonatschool.
3.Listenagainandlistthestudentssuggestionsforraisingmoney.
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
Suggestedanswers：1.Runsomecompetitionsatlunchtime.
2．Haveaconcertormovienight.
3．Haveabasketballmatch.
4．Haveapersonalchallenge，likegettingsomeonetosponsorstudentsforwalking25kilometres.
4．Listenagainandlistthewaysthestudentscouldgivetheirtime.
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
Suggestedanswers：1.ServesouptohomelesspeopleonFridays.
2．Visitoldpeopleandchildreninhospitaleveryweek.
3．Dosomethingfortheenvironment，liketreeplantingorcleaninguprubbish.
?Step5　Conclusion
T：Wehavelistenedtotwomaterialsaboutgivinghelptoothers.Idohopeallofuswillhelpthosewhoneedhelp.Remember：Youcanpredictwhatyouwillhearbeforelistening.Whilelistening，youshouldpayattentiontothetimeexpressionsinthepassagewhichisaboutsomepersonsexperiences.
Homework：
1．FinishtheListeningTaskonPages75－76.Trytopredictwhatyouwillhearaccordingtothegiveninformationandalsopayattentiontothetimeexpressions.
2．LookformoreinformationaboutMSFontheInternetandshareitwithyourpartner.

Unit4　Globalwarming

Unit4　Globalwarming

单元要览

本单元的中心话题是人类当今面临的环境问题，主要探讨了“全球变暖”和“节约能源”等方面的问题。由于人类过多使用不可再生能源，大气中二氧化碳的含量逐年增加，导致全球气温上升。通过学习本单元，让学生了解能源分为“不可再生能源”和“可再生能源”，帮助学生树立“节约能源、保护环境”的主人翁意识。

本单元的主要教学内容如下表所示：

类别

课程标准要求掌握的内容

话题

Globalwarming，pollutionandtheimportanceofprotectingtheearth

词

汇

tend

v.趋向；易于；照顾

catastrophe

n.大灾难；浩劫

oppose

v.反对；反抗；与(某人)较量

flood

n.洪水；水灾

state

v.陈述；说明

consequence

n.结果；后果；影响

glance

v.看一下；扫视　n．一瞥

existence

n.生存；存在

quantity

n.量；数量

commitment

n.承诺；交托；信奉

range

n.种类；范围

pollution

n.污染；弄脏

tendency

n.趋向；趋势

growth

n.增长；生长

circumstance

n.环境；情况

motor

n.发动机

opposed

adj.反对的，对立的

can

n.容器；罐头

steady

adj.平稳的；持续的

microwave

n.微波炉；微波

widespread

adj.分布广的；普遍的

educator

n.教育工作者；教育家

average

adj.平均的

contribution

n.贡献

consume

v.消费；消耗；耗尽；吃完

presentation

n.显示；演出

subscribe

v.同意；捐赠；订阅

disagreement

n.分歧；不一致

advocate

v.拥护；提倡；主张

random

adj.胡乱的；任意的

refresh

v.使恢复；使振作

mild

adj.温和的；温柔的；淡的

graph

n.图表；坐标图；曲线图

outer

adj.外部的

phenomenon

n.现象

electrical

adj.电的；与电有关的

fuel

n.燃料

casual

adj.随便的；偶然的

data

n.资料；数据

nuclear

adj.核的；核能的

trend

n.趋势；倾向

per

prep.每；每一

comeabout发生；造成

keepon继续

subscribeto同意；赞成；订购

onthewhole大体上；基本上

quantitiesof大量的

onbehalfof代表……一方；作为……的代言人

goup上升；增长；升起

putupwith忍受；容忍

resultin导致

solongas只要

beopposedto反对

andsoon等等

evenif即使

greenhouseeffect温室效应

句

型

1....it_ishumanactivitythathascausedthisglobalwarming...　(emphatic“it”)

2....itisarapidincreasewhen_compared_toothernaturalchanges.(ellipsis)

3.Thereisnodoubtthat_the_earth_is_becoming_warmer...(theappositiveclause)

4.Withoutthe“greenhouseeffect”，theearthwould_beaboutthirty－threedegreesCelsiuscoolerthanitis.(thesubjunctivemood)

功

能

1.同意与不同意(Agreementanddisagreement)

Exactly.Youreright.Iagree.Thatscorrect/true/right.

ImafraidIdisagreewithyou.Imafraidnot.Idontthinkso.

Noway.Idontagree.Idoubt...

2．责备与抱怨(Blameandcomplaint)

Imsorrytobringthisup，but...　Imsorrytohavetosaythis，but...

Theyshouldnthavedoneit.Theyaretoblame.

Perhaps/Maybetheyshould/oughtto...Whydontyoudosomethingaboutit？

语法

“it”的用法(theuseof“it”)(2)

...it_ishumanactivitythathascausedthisglobalwarming...

教

学

重

点

1.Getstudentstoknowaboutglobalwarminganditseffect；torealizewhatwecandoaboutglobalwarming.

2．Havestudentslearnsomeusefulnewwordsandexpressionsaboutglobalwarmingandletthemlearneffectivewaystomasterthem.

3．Enablestudentstograspandusetheexpressionsofagreementanddisagreement，blameandcomplaint.

4．Letstudentslearnthenewgrammaritem：theuseof“it”(2)．

5．Developstudentslistening，speaking，readingandwritingability.

教学难点

1.Enablestudentstomastertheuseof“it”(2)．

2．Letstudentslearntowriteashortpassagetotellothershowtosolvetheproblemofglobalwarming.

3．Developstudentsintegrativeskills.

课时安排

Periodsneeded：6

Period1　WarmingUp，Pre－reading，ReadingandComprehending

Period2　LanguageStudy

Period3　Grammar—theUseof“It”(2)

Period4　ListeningandSpeaking

Period5　ReadingandWriting

Period6　SummingUp，LearningTipandAssessment

Period1　WarmingUp，Pre－reading，

ReadingandComprehending

整体设计

教学内容分析　

Thisisthefirstteachingperiodofthisunit.Thecentralpartofthisperiodisthereadingpassagewiththetitleof“TheEarthIsBecomingWarmer—ButDoesItMatter？”talkingabouttheglobalissuewhichhasagreateffectonhumanbeingslife.

WarmingUpgivessixpicturestohelpstudentslistthesourcesofenergytheycanthinkofinourdailylife.Thentheywillbeledtodiscusswhichenergysourceis“renewable”andwhichis“non－renewable”．Thispartisdesignedtohelpthestudentstorecalltheirbackgroundknowledgeaboutenergyandpreparesstudentsforthewholeunit.

Pre－readingprovidesapictureofagreenhouseandthentellsuswhatagreenhouseisandwhat“greenhousegases”are.Thestudentswillbeledtodiscusswhattheythinkgreenhousegasesdo，leadingtothetopicofthereadingpassage.

Readingisapassagefromanenvironmentalmagazineforyoungpeople.Itputsforwardthepossibleeffectofincreasedcarbondioxideintheatmosphereanddifferentpointsofviewaboutit.Italsoanalyzesthecausesoftheearthsincreasedtemperature.Itposesquestionsandencouragesstudentstothinkabouttheissues.Therearetwographsinitthattellusthe“temperaturedifferencefromlong－termaverage,1860－2000”and“carbondioxidecontentintheatmosphere,1957－1997”．Charactersinthepassage—DrJaniceFoster，GeorgeHambleyandCharlesKeelingareallrealpersonsandtheirviewsreflecttheviewsofsomescientiststoday.

Comprehendingconsistsofthreewrittenororalexercisesforthestudentstodosoastohelpthestudentstogetabetterunderstandingofthetext，thatistosay，tohelptheteachertocheckhowmuchthestudentshaveunderstoodthetext.

三维目标设计　

Knowledgeandskills

1．Toknowthemeaningsofthefollowingnewwordsandphrases：

consume(消费；消耗；耗尽)，comeabout(发生；造成)，random(胡乱的；任意的)，phenomenon(现象)，subscribe(同意；捐赠；订阅；签署文件)，subscribeto(同意；赞成；订购)，fuel(燃料)，quantity(量；数量)，quantitiesof(大量的)，tend(趋向；易于；照顾)，goup(上升；增长；升起)，per(每；每一)，data(资料；数据)，resultin(导致)，trend(趋势；倾向)，catastrophe(大灾难；浩劫)，flood(洪水；洪灾)，oppose(反对；反抗)，opposed(反对的；对立的)，beopposedto(反对)，consequence(结果；后果)，state(陈述；说明)，range(种类；范围)，evenif(即使)，keepon(继续)，glance(看一下；扫视)，steady(平稳的；持续的)，steadily(平稳地，持续地)

2．Tolearnaboutsomefactsandviewsaboutglobalwarming.

3．Tolearnhowtheinformationisorganized.

4．Todevelopthestudentsreadingabilitybyskimmingandscanningthepassage.

5．Todevelopthestudentsspeakingabilitybytalkingaboutglobalwarming.

Processandmethods

1．WhiledoingWarmingUptheteachercanleadinthetopicofthisunitbyshowingstudentssomepicturesorvideosaboutsourcesofenergy，makingthestudentsrecalltheirownknowledgeaboutenergy.

2．DuringPre－readingtheteachercangoaroundtheclassroomanddiscussthequestionswithseveralstudents.Thisdiscussionshouldbestudent－centeredandleadthemtothetopicofglobalwarming.Theteachershouldalsoaskthestudentstolookatthegraphsinthereadingpassageandtrytofindoutthegeneralideaofthetext.

3．WhiledoingReadingandComprehending，theteachermayfirstaskthestudentstoreadthetextquicklytogetthegeneralideaofeachparagraph.Afterreadingthepassage，studentsareencouragedtoanswersomequestionsanddiscussthetextstructure.

4．Toconsolidatethecontentsofthereadingpassage，thestudentsshouldberequiredtoretellthetextintheirownwordsattheendoftheclass.

Emotion，attitudeandvalue

1．Tomakestudentsrealizetheharmofglobalwarmingandtheimportanceofenvironmentalprotection.

2．Todevelopstudentssenseofcooperativelearning.

教学重、难点　

1．Toenablethestudentstolearnaboutglobalwarmingandtodeveloptheirreadingability.

2．Toenablethestudentstotalkaboutwhatweshoulddotopreventglobalwarming.

教学过程

?Step1　Warmingup

1．Warmingupbyreadingandtalking：

Readthroughtheexercisewiththeclass.Putstudentsingroupsoffourtotalkaboutwhatweuseenergyfor，whatarethesourcesoftheseenergyandwhetherthesourcesarerenewableornon－renewable.

Suggestedanswer：Thesixphotosare：windmills；acoalpowerstation；anoilrefinery；anuclearpowerplant；solarpanels；ahydro－electricdam.

2．Warmingupbydiscussion：

Drawaformontheblackboardasfollows：

Thingsthatuseenergy

Sourcesofenergy

Renewable/non－renewable　Letthestudentshaveadiscussionandcollectsuggestionsfromstudentsandwritethemundertheappropriateheading.

Suggestedanswer：

Thingsthatuseenergy

Sourcesofenergy

Renewable/non－renewable

lights

heating

television

cassetteplayer

videorecorder

computer

fridge

stove

hairdryer

...

coal

non－renewable

oil

non－renewable

naturalgas

non－renewable

windpower

renewable

solarenergy

renewable

nuclearenergy

non－renewable

hydro－electricpower

renewable

biomassenergy

renewable

geothermalenergy

renewable

tidalenergy

renewable?Step2　Pre－reading

1．Showapictureofagreenhousetostudentsandaskthemwhatagreenhouseismadeofandwhatitspurposeis.

Suggestedanswer：Itsmadeofglassandplantscangrowinitwhenitscoldoutside.

Askthestudentshowitworks.

Suggestedanswer：Theglasstrapstheheatfromthesun，makingtheairwarmsothatplantsgrowbetter.

2．Askstudentswhattheythink“greenhousegases”areandwhattheythinkgreenhousegasesdo.Lookatthepictureaboveandexplainittotheirpartners.

Suggestedanswer：Greenhousegasesperformthesamefunctionastheglassinaglasshouse：theytraptheheatofthesunandkeeptheairsurroundingtheearthwarm.Thisiscalledthegreenhouseeffect.)

?Step3　Readingandcomprehending

1．Fastreading

Askstudentstoreadthepassagequicklysoastogetthekeywordsandgeneralideaofeachparagraphandanswerthefollowingquestions：

(1)Whatisthemaintopicofthearticle?

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(2)Whowrotethemagazinearticle？Whatisthenameofthemagazine?

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(3)Whatarethenamesofthethreescientistsmentionedinthearticle？Dotheyagreewithoneanother?

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Suggestedanswers：(1)Globalwarming/thewarmingoftheearth.(2)SophieArmstrong，EarthCare.

(3)DrJaniceFoster，CharlesKeeling，GeorgeHambley.Theydontagreewitheachother.

2．Detailedreading

(1)Readthepassagecarefullyandjudgewhetherthestatementsaretrue(T)orfalse(F)．

①JaniceFosterbelievesthatglobalwarmingiscausedbytheburningfossilfuels.(　)

②Naturalgasisagreenhousegas.(　)

③Carbondioxideisabyproductofburningfossilfuels.(　)

④PeopleacceptCharlesKeelingsdatabecausehetookaccuratemeasurements.(　)

⑤Floodingcouldbeoneoftheeffectsoffutureglobalwarming.(　)

⑥GeorgeHambleybelievesscientistsarejustguessingabouttheeffectsofglobalwarming.(　)

⑦GeorgeHambleyisworriedabouttheeffectsofcarbondioxideonplantgrowth.(　)

⑧Itisclearwhattheeffectsofglobalwarmingwillbe.(　)

(Suggestedanswers：TFTTTTFF)

3．Structureanalyzing

Askstudentstoreadthetextcarefullyandtrytofindouthowmanypartstheycandividethetextintoandfindoutthemainideaofeachpart.

Part

Mainidea

Part1(Paragraph______)

Part2(Paragraphs______to______)

Part3(Paragraphs______to______)

Part4(Paragraph______)Suggestedanswer：

Part

Mainidea

Part1(Paragraph1)

Tointroduceadebateovertheissueofglobalwarming.

Part2(Paragraphs2to5)

Toillustratehowglobalwarmingcomesabout.

Part3(Paragraph6)

Tolisttwodifferentattitudesamongscientiststowardsglobalwarming.

Part4(Paragraph7)

Itsuptoreaderstothinkanddecidewhetherpeopleshoulddosomethingaboutglobalwarmingornot.?Step4　Languagestudy

Dealingwithanylanguageproblemifany(wordsorsentencesstudentsmightnotunderstand)tohelpthestudentstohaveabetterunderstandingofthetext.

?Step5　Listening，readingaloudandunderlining

Askstudentstoreadthepassagealoudtothetapeandletthempayattentiontothepronunciationofeachwordandthepauseswithineachsentence.Tellthemtopickoutalltheusefulexpressionsorcollocationsfromthepassagewhilereadingandcopythemtothenotebookafterclassashomework.

Collocations：comeabout，Thereisnodoubtthat...，subscribeto，dueto，greenhouseeffect，quantitiesof，tendto，betrappedin，goup，resultin，ontheonehand...ontheotherhand，beopposedto，buildup，keepon.

?Step6　Retelling

Askstudentstotalkaboutglobalwarmingintheirownwords.Givethemsomekeywordsandexpressionsontheblackboard.Thenletthemtrytoretellthepassage.

?Step7　Homework

1．Learntheusefulnewwordsandexpressionsinthispartbyheart.

2．TrytofindsomedataaboutglobalwarmingontheInternet，andshowyourclassinthenextperiodandtalkaboutthem.

?Step8　Reflectionafterteaching

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教学参考

AboutGlobalWarming(关于全球变暖)

GlobalwarmingistheincreaseintheaveragetemperatureofEarthsnear－surfaceairandoceanssincethemid－20thcenturyanditsprojectedcontinuation.Globalsurfacetemperatureincreased0.74±0.18℃(1.33±0.32?)betweenthestartandtheendofthe20thcentury.TheIntergovernmentalPanelonClimateChange(IPCC)concludesthatmostoftheobservedtemperatureincreasesincethemiddleofthe20thcenturywasverylikelycausedbyincreasingconcentrationsofgreenhousegasesresultingfromhumanactivitysuchasfossilfuelburninganddeforestation.TheIPCCalsoconcludesthatvariationsinnaturalphenomenasuchassolarradiationandvolcaniceruptionshadasmallcoolingeffectafter1950.Thesebasicconclusionshavebeenendorsedbymorethan40scientificsocietiesandacademiesofscience，includingallofthenationalacademiesofscienceofthemajorindustrializedcountries.

ClimatemodelprojectionssummarizedinthelatestIPCCreportindicatethattheglobalsurfacetemperatureislikelytoriseafurther1.1to6.4℃(2.0to11.5?)duringthe21stcentury.Theuncertaintyinthisestimatearisesfromtheuseofmodelswithdifferingsensitivitytogreenhousegasconcentrationsandtheuseofdifferingestimatesoffuturegreenhousegasemissions.Moststudiesfocusontheperioduptotheyear2100.However，warmingisexpectedtocontinuebeyond2100evenifemissionsstop，becauseofthelargeheatcapacityoftheoceansandthelonglifetimeofcarbondioxideintheatmosphere.

Anincreaseinglobaltemperaturewillcausesealevelstoriseandwillchangetheamountandpatternofprecipitation，probablyincludingexpansionofsubtropicaldeserts.WarmingisexpectedtobestrongestintheArcticandwouldbeassociatedwithcontinuingretreatofglaciers，permafrostandseaice.Otherlikelyeffectsincludechangesinthefrequencyandintensityofextremeweatherevents，speciesextinctions，andchangesinagriculturalyields.Warmingandrelatedchangeswillvaryfromregiontoregionaroundtheglobe，thoughthenatureoftheseregionalvariationsisuncertain.

Politicalandpublicdebatecontinuesregardingglobalwarming，andwhatactions(ifany)totakeinresponse.Theavailableoptionsaremitigationtoreducefurtheremissions；adaptationtoreducethedamagecausedbywarming；and，morespeculatively，geoengineering(地球工程)toreverseglobalwarming.MostnationalgovernmentshavesignedandratifiedtheKyotoProtocolaimedatreducinggreenhousegasemissions.

文章来源：http://m.jab88.com/j/43243.html

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