人教版高中英語Unit19Modernagriculture教案

1、Unit19ModernagricultureI.TeachingGoals:1 .Talkaboutmodernagricultureandtheeffectsithasonpeople'slife.2 .Practisegivingadviceandmakingdecisions.3 .Use“It”foremphasis.4 .Readstatisticalgraphs.5 .Writeaplanforavegetablegarden.n.TeachingTime:Fiveperiodsin.BackgroundInformation:1 .AnAmericanSmallFarm

2、Lastyear,atharvesttime,wevisitedtheSteenhoekfarm,whichis2200mu,or340acres.Typicalfamilyfarmsarerunentirelybyfamilymembers,witheverymemberplayingavitalpartintheoperation.BothofthesefamiliesaredescendantsofDutchimmigrantswhosettledhereoveracenturyago.TheSteenhoekfarmsupports3generations.ThefamilyofMr.

3、andMrs.Steenhoekincludesthreechildrenand2grandchildren.Aswewillsee,thisfamilyisanexcellentexampleofhardworking,experiencedfarmerswhostayonthelandnotpurelybecauseofprofit,butbecausetheyarelivingalife-stylethatsatisfiesthem.SixtypercentoftheSteenhoek'sacresaredevotedtopastureland,onwhichtheyraise1

4、20beefcattle.Therestofthelandisusedforgrowingcorn.Fifteenyearsago,theAmericanfarmeconomywasbooming.Farmerscouldspecialize,raisingonecrop,oronetypeofanimal.Today,withanuncertainfarmeconomy,suchanideaisconsideredfoolhardy,anddiversifyingisonewaythatfarmerscanlessontheirriskofloss.Forexample,ifweathera

5、ffectsthesizeofacrop,thesaleofthelivestockwillmakeupthedifference.Iftheanimalsareplaguedbydisease,atleastthereisgraintotaketomarket.KendallSteenhoek,Simon'seldestson,divideshistimebetweenrunningthismachineshopandfarmingzooacresofcorn.HeattendedacommunitycollegeinIowafortwoyearstostudydieselmecha

6、nics.Thenheopenedthisrepairshopforfarmmachinery.Kendallalsoplantsandharvestsover30000bushelsofcorneachyear,butitistheincomefromtherepairshopthathasenabledhimtostaywithinthefarmingcommunity.Theheavyequipmentusedonthefarmstodayisinconstantneedofmaintenance,andrequiresprecisiontoolingforrepairs.Byfar,t

7、hemostimpressiveandcertainlythemostcostlypieceoffarmequipmentusedonasmallfarmisaharvestingmachinecalledacombine,whichcancostupto$100000.ThistypeofmachineryiswhatmakestheAmericanfarmsoefficient.Withacombine,onemanandhisfamilycanharvestanentirecropofa500acrefarmintwoweeks.Thevalueofthecombineisthatitp

8、erformsseveralfunctions.Asitmovesthroughafieldofcorn,thissophisticatedmachinecutsthestalk,pluckstheear,discardsthestalk,shucksthecornkernelsofftheearanddepositesthekernelsinastoragebinintheback.Then,aspinningdeviceintherearofthecombineshredsthehusksandshaftsandscattersthemacrossthefield,toserveasmul

9、ch,cuttingdownonthepossibilityofsoilerosionfromwinterrains.ThemachineisevenmoreamazingwhenyouthinkthatithasbeeninuseonAmericanfarmsforonlyonegeneration.2.GenesEverylivingcellcontainsgenes.Theyaretoosmalltobeseeninamicroscope,buttheyarevitallyimportant.Eachsetofgenesinthebodycontainsalltheinstruction

10、sneededtomakeahumanbeing.Somegenesdeterminehaircolor.Somedeterminetheshapeofanose.Somegeneshelpdetermineyourheightandevenyourweight.GenesaremadeofachemicalcalledDNAthelettersstandfordeoxyribonucleicacid（脫氧核糖核酸）.Intheearly1950's,twoscientists,FrancisCrickandJamesWatson,figuredouthowthepartsofDNAf

11、ittogether.Oncescientistsunderstoodthisstructure,itbecamepossibletotakepiecesofDNAapartandputthemtogetherinnewways.Newkindsofgenescouldbemadeinthismanner.Scientistshavestudiedthegenesofmanyplantsandanimals.Theyhaveworkedoutwhichgenesaffectthecolorofatomatoandthesticknessofitsskin.Workingoutwhichgene

12、sdeterminewhichfeaturesiscalledgeneticmapping,scientistshavebeguntheHumanGenomeProject,anambitiousefforttomapallthegenesinthehumanbody.Somegenesmaybeeffective.Forexample,somethingmightbewrongwiththegenethatmakesbloodclot（凝聚）.Anindividualbornwiththisdefectivegenecouldsufferserioushemorrhages（出血）oreve

13、nbleedtodeathbecausehisorherbloodfailstoclot.Ifscientistseverlearnhowtomapallthegenesinourbodies,theycoulddeterminewhetherornotanunbornchildhasanydefectivegenes.Theymightevendiscoverhowtotreatthesegenesbeforethechildisborn.TheFirstPeriodTeachingAims:1.1 mprovethestudents'speakingabilitybypractis

14、inggivingadviceandmakingdecisions.2 .Enablethestudentstomastertheexpressionsofgivingadviceandmakingdecisions.3 .Getthestudentstolearnmoreaboutagriculture.TeachingImportantPoints:1 .Howtoexpressoneself,usingwhatislearnedorgiven.2 .Howtoadvisesb.todosomethingandhowtomakedecisions.TeachingDifficultPoin

15、ts:1 .Theusageofsomeexpressions.2 .Howtoimprovethestudents'listeningability.TeachingMethods:1 .Listeningsomematerialstoimprovethestudents'listeningability.2 .Discussiontoletthestudentsexpressthemselvesfreely.3 .Groupworkorpairworktogiveeverystudentachancetoexpressthemselves.TeachingAids:1 .a

16、taperecorder2 .aprojectorandsomeslides3 .acomputerTeachingProcedures:stepI.GreetingsandRevisionT:Goodmorning,everyone.Ss:Goodmorning,teacher.T:Sitdown,please.Inthisclass,I'llcheckyourhomeworkfirst,WangPing,readyourhomeworktous,(Theteacherchecksthestudents'homeworkandhaveadiscussionwiththestu

17、dentsaboutthemistakeWangPingmade.Letthestudentshaveaclearunderstandingandcorrectit.)stepn.PreparationforlisteningandspeakingT:Today,we'regoingtolearnanewunit,Unit19,ModernAgriculture(Teacherwritesthefollowingontheblackboard:Unit19Modernagriculture,theFirstPeriod).First,let'slearnthenewwordso

18、fthisperiod.Lookatthescreen:Newwords:producen.產(chǎn)量、產(chǎn)物、農(nóng)產(chǎn)品effectn.結(jié)果、影響、作用diken.堤壩；排水溝droughtn.干旱leadern.領(lǐng)導(dǎo)者leadv.領(lǐng)導(dǎo)、帶領(lǐng)canen.細(xì)長的莖、藤條sugar-canen.甘蔗t(yī)obaccon.(煙草)制品;抽煙localadj.地方的、當(dāng)?shù)氐?Teacherasksonestudenttoreadthenewwords,thencorrectsthemistakesthestudentmade.)Stepin.WarmingupT:PleaseturntoPage32.Let'

19、;sdoWarmingup.(TeachershowsthegraphsonPage32onthescreen.)LookatthetwographsanddiscussthequestionsonPage32.Youcandoitinpairsorgroups.Inafewminutes,I'llasksomestudentstotalkaboutthem.(Studentsbegintodiscussthequestions.Andteachergoesandjoinsthem.Afewminuteslater,teachersaysthefollowing.)T:Areyoure

20、ady?Whocangiveusatalkaboutthefirsttopic?SA,howarepeople'seatinghabbitschangingovertheyears?SA:Fromthefirstgraph,wecanseethattheeatinghabitsofthepeopleinourcountryhavechangedgreatly.Before1949,theyhadnotenoughtoeatandoftenwenthungry.Oncenaturaldisastershappened,agreatnumberofpeoplewoulddieofhunge

21、r.Beforethereformingandopeningtotheworld,grainwasstillabigproblem.Peoplemainlylivedoncornandfewkindsofvegetables.Sincethe1980s,especiallythe1990s,people'seatinghabitshavegreatlyimproved.Peoplecaneatwhatevertheywant.Moreandmorepeopleeatlessgrain,moremeatandeggsandsoon.Moreandmorepeopleturntheirey

22、estomeat,eggs,milkandallkindsofgreenvegetables.T:Whydoyouthinkthishappens,Sb?SB:ItisallbecauseoftheParty'sgoodpolicies.T:Verygood.Itistrueandeveryonecanseethat.Howhasagriculturalproducechangedduringthefirsthalfofthe1990s?Andwhatdoyouthinkcausedthesechanges?ScFromthefirsthalfofthe1990s,scientists

23、startedtodevelopnewtechniquestoincreaseagriculturalproductionwithoutcausingdamagetotheenvironment.Especiallythenewtechnique,"GM",hasmadeagriculturalproductionincreasecontinuously.Scientistsdevelopnewkindsofseeds,bettercows,pigs,sheepaswellasfish.Itisthenewtechniquesthatmakeallthispossible.

24、T:Doyouagreewithhim,SD?Sd:Yes,Ido.AndIwanttogiveananswertothethreequestion.T:Good,pleasesaythat.Sd:Withthechangesinpeople'seatinghabits,agricultureaswellasnaturewillhavetochange,too.Peopleareeatingmoremeatandmilk.Thatistosay,theyneedmorefish,pigs,sheepandcattleaswellaspoultry.Tofeedtheseanimals,

25、weneedmoregrain,especiallymoregrass.Toprotectourenvironment,thewaystoraiseanimalshavechanged.Withthedevelopmentofmodernscienceandtechniques,someofthefieldsarenotneededtoproducemorefood.Wecangrowgrass,flowersetc.onthem.Lessfarmersareneededandtheycandootherkindsofwork.StepIV.ListeningT:Somuchforthedis

26、cussion.Nextwe'lldolistening.Thepassageyou'lllistentoisaboutfarming.Ittellsusaboutfarmingofallcountriesinearlytimesandprotectionofnatureandenvironment.Listentothetapecarefullyanddotheexercisesconcerned.Now,readtherequirements,please.(Studentsreadtherequirements.)Nowdoyouknowwhatyou'llhav

27、etodoafterlisteningtothepassage?(Ss:Yes.)Duringlistening,I'llplaythetapethreetimes.Afterlisteningforthefirsttime,youcanleaveovertheonesyouarenotsureabout.YoucandothemwhenIplaythetapeforthesecondorthethirdtime.Checkyouranswerswithyourpartnerafterlistening.Areyouclear?(Ss:Yes.)(Atlast,teachershows

28、theanswersonthescreen.)StepV.SpeakingT:Nowlet'sdospeaking.Thispartsaysthatagroupoffarmersinyourareahavebeengivenalargepieceofland.Thevillagerstogetherwiththevillageleaderhavetodecidehowtousetheland.Workingroupsoffivestudents.Eachgroupmemberwillplayoneoftheroles.Preparerolecards,discusstheproblem

29、andtrytomakeadecision.Beforediscussion,whocangiveussomeusefulexpressionsaboutgivingadviceandmakingdecisions?Givingadvice:SE：Myadvicewouldbe.Iadviseyoutodo.Sf：Ithinkyououghtto.You.dbetter.SG:IfIwereyou,Iwould.Iwouldadviseyou.Sh:Idon'tthinkyououghtto.Makingadecision:SrInmyopinion,weshouldIthink/be

30、lieveyoushouldSj：Idon'tthinkitisnecessarytodosth.Wemustdecide.Sk:Ihopewecanmakeadecision.(TeacherwritesalltheexpressionsaboveontheBb.)T:Nowlet'shaveadiscussion,usingtheexpressionsontheblackboardlater,I'llasksomestudentstoactitout.Samplediaolgue:SavillagerA;SbvillagerB;ScvillagerC;Sdvilla

31、gerDSethevillageleaderSe：Asweallknow,wearegivenalargepieceofland.I'vegotallofusheretohaveadiscussionanddecidehowtousetheland.Pleasegiveusyouradvice.Sa：Iadviseweshouldgrowcornonthispieceofland.It'slargeandflatandmachinescangoupanddownit,sowecanspendlesstimeandgetmorecorn.Alotofmoneycanbemadea

32、ftersellingthecorn.Sb:Ithinkweoughttobuildafarmthereandraisepigsorcowswiththegrainweharvest.Sowecanmakemoremoney.Sc:Myadviceisthatweshouldturnitintoagarden,andgrowflowersthere.Thenwecanselltheflowers.Thereisnobodyheresellingflowers.SoIthinkourbusinesswillsurelybegood.Besides,sometimessellinggrainorm

33、eatishard,forthepricecouldbetoolow.Sd:Ithinkwe'dbetterdesignitlikethis:Webuildabuildingofafewfloors.Ineachfloor,wecanraiseonekindofanimals.Withtheirwastes,wecanraisefishorgrowvegetablesonthetoporinthespacewhichfacesthesun.Wecanalsogrowmushroomsinthedarkplaces.Wecanuseonequarterofittodothisandbui

34、ldagardenononequartersothatpeoplecanenjoythemselveshere.Halfoftherestgrowflowerstosellandfortheotherhalfwecangrowgrassonitsothatourenvironmentwillbebetter.Sa:That'sagoodidea.Butitwillneedalotofmoneytodothis.Ihopewecanmakeadecisiontoday.Se:Wemustmakeadecision.MyopinionisthatwedoasSdsaid.Anyothero

35、pinions?SbandSc:Iagreewithyou.StepVI.SummaryandHomeworkT:Inthisclass,we'vetalkedabouttwostatisticalgraphsandlistenedtoapassage.Wehavealsotalkedabouthowtousealargepieceofland,usingsomeexpressionsofgivingadviceandmakingdeicisions.Theseexpressionsare:“"(Pointingtotheblackboard.)Afterclass,choo

36、seasubjectasyoulikewithyourpratnerandhaveadiscussion,usingtheexpressionsontheblackboard.That'sallfortoday.Classisover.Step叩.TheDesignoftheWritingontheBlackboardUnit19ModernagricultureTheFirstPeriodGivingadvice:Myadvicewouldbe.Iadviseyoutodo.Ithinkyououghtto.You'dbetter-.IfIwereyou,Iwould.Iwo

37、uldadviseyou.Idon'tthinkyououghtto.Makeadecision:Inmyopinion,weshould.Ithink/believeweshould.Idon'tthinkitisnecessarytodosth.Wemustdecide-1.Ihopewecanmakeadecision.StepW.RecordafterTeachingTheSecondPeriodTeachingAims:1 .Enablethestudentstolearnsomethingaboutmodernagriculturefromthetext.2 .En

38、ablethestudenttomasterthenewwordsandexpressionsinthetext.3 .Getthestudentstohavetheabilitytograspthegeneralideaofanpassageasfastaspossible.TeachingImportantPoints:1 .Howtoimprovethestudents'readingability.2 .Howtogetthestudentstomasterthenewwordsandexpressionsofthetext.TeachingDifficultPoint:How

39、toimprovethestudents'readingandwritingability.TeachingMethods:1 .Discussiontoraisethestudents'interestinagriculture.2 .Ask-and-answermethodtohelpthestudentsunderstandthetextbetter.3 .Freetalktoimprovethestudents'speakingability.TeachingAids:1 .ataperecorder2 .aprojectorandsomeslides3 .ac

40、omputerformultimediauseTeachingProcedures:stepI.GreetingsandRevisionGreetthewholeclassasusualT:Attheendofthelastperiod,Iaskedeveryoneofustojoininadiscussion.NowI'llaskagrouptorepeatthediscussion.Whowillactitoutforus?WangHong,actitforuswithyourgroup,willyou?Wang:Yes.(Teacheraskstwogroupstorepeatt

41、heirdiscussionbeforetheclass.)stepn.PreparationforReadingT:Somuchforrevision.PleaseturntoPage113.Let'slearnthenewwordsandexpressionstogether.LiMing,readthenewwordsandexpressionsofthisperiod,please.Beginwiththeword“arable”andendwiththeword“soil”.(Teacherandthestudentslearnthenewwordsandexpression

42、stogether.Teachercorrectsstudents'mistakesinpronunciationandgivessimpleexplanationsofsomewordsifnecessary.)T:Arethereanystudentscomingfromthecountrysideinourclass?Ss:Yes.Alotofusstudentsarefrompeasantfamily.T:Haveyoueverworkedinthefields,WangFei?Wang:Yes.Ioftenworkinthefieldwithmyparents.Icandoa

43、lotoffarmwork.T:Haveyoueverheardofanythingaboutfarminginthepast?Ss:Yes,Ihave.T:NowturntoPage34.Let'sdopre-reading.Discussthequestions.Groupwork.Writeyouranswersonapieceofpaper.(Afterafewminutes.)T:Areyouready?(Ss:Yes.)Whowouldtellussomethingabouttraditionalandmodernfarming?SA:Inthepast,farmersgr

44、owcropsinthetraditionalway:Usecattletoploughthefieldfarmersworkinthefieldmostofthedayallyearround,buttheycouldnotproduceenoughfoodforthewholepopulation.Nowtheygrowcropsinthemodernway.Theyusemoderntechniquesintheirfields,suchaschemicalfertilizers,greenhousesandsoon.T:Whowouldanswerthesecondquestion?S

45、b：I'11try.Theadvantagesare:chemicalfertilizers,electronicpumpsandotheradvancedtechnologyareused.Farmerscanspendlesstimeonfarmsandmuchmoregrainisproduced.Thedisadvantagesare:theair,thewaterandthesoilroundusaremoreorlesspolluted.Sc:I'llsaysomethingaboutotherchangesthathavetakenplaceonfarmsinth

46、elast100years.Inthepast,wedependedonheavenandwecoulddolittlewhennaturaldisastershappened.Now,wecandoartificialrainfall.GMmakesbetterseedspossible.Inthesamefields,betterseedscangiveusmuchmoregrain.Besides,allkindsofscientificwaysoffarmingareusedinfarming.Farmersinourcountryarebecomingricherandricherd

47、aybyday.T:Verygood.Stepin.FastReadingT:Nowreadthetextfastandthenanswerthequestionsonthescreen.1 .Whenwasmoreadvancedtechnicalinformationwasbroughtinfromabroad?2 .Whatisimportantforfutureagriculture?Whatshouldfutureagriculturedependon?3 .Whatdoes“which"refertointhelasttwolines?(Afterafewminutes.

48、)T:Areyouready?Ss:Yes.T:Pleasegiveustheanswerstothequestions.SD:Inthe1980s,moreadvancedtechnicalinformationwasbroughtinfromabroad.SE:Bothfoodproductionandtakingcareoftheenvironmentareimportant.Andfutureagricultureshoulddependonhightechnologyaswellastraditionalmethods.Sf：Ithinktakingcareoftheenvironm

49、entismoreimportant.Becausewehaveonlyoneearth.Sa:Inthelasttwolines,“which"refersto“goldenrice".T:Whatistheothernameof“goldenrice"inthetext?Sa:GMrice.StepIV.ReadingT:NowreadthetextagainandanswerthequestionsinPostReading.Ifyouarenotsureaboutyouranswers,haveadiscussionwithyourclassmates.(

50、Afterthestudents'discussion)T:PleaseturntoPage35.Let'sanswerthequestions.SH,giveyouranswerstothefirstfivequestions.SH：Theyare:1.D2.A3.C4.C5.CT:Isheright?Ss:Yes,heisright.T:Nowlet'sdoPart2.Si：Iwanttochangeapples.Iwantthemnotonlytogrowbiggerandmoredelicious,butalsoofthesamesize.Becausesome

51、oftheapplesnowaresmallerandnotdeliciousandtheapplesofthesamesizearepopularinthemarket.Sj：Iwanttochangefruittrees.Iwantthemtogrowshortersothatthefruitsonthemareeasytopickup.Andtheymustgiveusmorefruitssothatthefarmerscanmakemoremoneyandbecomericher.T:That'sagoodidea!Ihavethesameopinionasyou.Sk：Iwa

52、nttochangecarrots.Iwantthemtogrowmuchbigger.Becausethecarrotsourvillagersgrowaresmaller.Sl:Iwanttochangethevegetablespeopleusuallyeat.Iwantthemtobebetterforpeople'shealth.Sotheywillspendlessmoneyonmedicine.Sm:Iwanttochangecows.Iwantthemtohavemorebabies.Sotheywillnotbeexpensivetobuy.Ifso,morefarm

53、erscanbuythemandbecomerich.Sn:Iwanttochangefruittrees.Iwanttoplantthetreesgrowinginthesouth.Sowewillhavemorekindsoffruitsthaneverbefore.T:You'vedonewell.Afterclass,continuetothinkaboutmoregoodideas.NowI'llexplainsomeexpressionsandlanguagepointsofthetexttoyou.Please100katthescreen.modernizev.

54、tomake(sth.)suitableformodernuseorfortheneedsofthepresenttime.e.g.Hespentalotofmoneymodernizinghishouse.dependon:Healthdependsongoodfood,freshairandenoughsleep.shortof:Hedidn'tbuyanythingbecausehewasshortofmoney.controlvhavepowerover(sb.orsth.),rule,directThemachineiscontrolledbythisbutton.contr

55、olone'sangerstandfor:USAstandsfortheUnitedStatesofAmerica.modify:tochange(sth,suchasaplan,anopinion,acondition,)Tomodifyanythingistochangeitalittle.T:(Afterexplainingthewordsandexpressionsonthescreen.)Nowreadthetextandseeifyoustillhavesomethingyoufinddifficulttounderstand.(Teachergoesamongthestu

56、dentstoexplainanyquestionsraisedbythestudents.)StepV.ListeningandReadingAloudT:Let'slistentothetape.I'llplayittwice.ThefirsttimeIplayit,justlisten.WhenIplayforthesecondtime,youcanreadthetextafterit.ThenpleasereadthetextaloudafterIplaythetape.(Whilethestudentsreadthetext,teachergoesamongthest

57、udentsandcorrectsanymistakesthestudentsmakeinpronunciationandintonation.)StepVI.SummaryandHomeworkT:Inthisclass,we'velearntthetext“Modernagriculture”.Ittellsusaboutagricultureofourcountry,forexample,itspastandpresent,especiallyitsfuture.Haveyouhadaclearunderstandingaboutfutureagriculture?Fromnow

58、on,weshouldstudyhardandbereadytomakegreatercontributionstoouragricultureandfarmers.Afterclass,pleasereadthetextagainandmastertheusagesofthenewwordsandexpressionsofthetext,especiallythefollowing:modernize.Youcanmakesentenceswiththeminpairsorgroups.That'sallfortoday.Classisover.StepW.TheDesignofth

59、eWritingontheBlackboardUnit19ModernagricultureTheSecondPeriodNewwords:modernize,control,modify.Usefulexpressions:dependon:Healthdependsongoodfood,freshairandenoughsheep.shortof:Hedidn'tbuyanythingbecausehewasshortofmoney.standfor:USAstandsfortheUnitedStatesofAmerica.StepW.RecordafterTeachingTheThirdPeriodTeachingAims:1 .Getthestudentstomasterthestructure:Itisthat.2 .