人教版高中英语教案选修七Unit3UndertheseaPeriod7

1Period7ListeningTask，TalkingandWritingTeachingaims1．Studentswillbeabletofindoutthereasonswhythepopulationofsharksdecreasessharply.2．Studentswillbeabletoexpressopinionswiththepoliteexpressionslike：Idon'tthinkitiswiseto...Itwouldbebetterifwe...Itisagoodideato...Isupposeitisright...Iwonderif...3．Studentswillbeabletopersuadethelocalgovernmenttoprotectwildlifeinapoliteway.Teachingprocedures1BeforelisteningShowstudentsapictureofsharkandtellthemafactthatsharkpopulationsaredecreasingrapidly.2DuringlisteningTask1：TellstudentsJordonDaviesisinterviewingthesharkexpertDonJamesaboutthesharks'situation.Firstreadthestatementsbelow.Thenlistenandnumberthesestatementsintheorderthattheyhearthem.□Sharkpopulationsgrowataveryslowrate.□Alotarekilledbecauseofmodernfishingtechnology.□Governmentsshouldtakeactionsothatthefishingofsharksissloweddown.□Sharkattacksgetalotofattentioninthenews.□Sharkpopulationsaredecreasingataseriousrate.□Somespeciesneedtobeprotected.□Thechanceofbeingbittenbyasharkisactuallyverysmall.□Millionsofsharksarekilledeachyear.Keys：theorder：74815623Task2：Listenagainandanswerthefollowingquestions：1．Shouldpeoplebeafraidofswimminginthesea?2．Howmanypeoplearekilledbysharkseachyear?3．Dosharksorpeopleneedtobeprotected？Why?4．Whyaresomanysharksbeingkilled?5．Whydoestheshark'sbiologyaffectsharkpopulations？Completethesentencesblow.A：Ageforreproducingyoung________________________________________________________________________B：Timefortheyoungtodevelop________________________________________________________________________C：Numberofyoung________________________________________________________________________6．Howlonghavesharkspeciesbeeninexistence?7．WhatdoesDonthinkwillhappenifwedon'tslowdownthefishingofsharks?2Suggestedanswers：1．No.2．Onlyafew.3．Sharksneedtobeprotectedasmillionsarekilledeachyearbyhumanbeings，whereasonlyafewhumanbeingsarekilledeachyearbysharks.4．Sometimestheyarekilledbyaccidentandsometimesonpurpose.Forexample，sharkfinsoupisadelicacyinsomeAsiancountries.5．15years；14months；7－9.6．400millionyears.7．Donthinksthatmanysharkspecieswillnotbeabletosurvive.3Post－listening(talking)Askstudentstomakeupadialogueaccordingtothesituationbelow.SupposeyouwereacitizeninacoastalcityinChina，sharkhuntisaseriousprobleminyourprovince.Trytopersuadethelocalgovernmenttotakeactiontoprotectwildlifeinapolitewaywiththehelpofthefollowingexpressions：Idon'tthinkitiswiseto...Itwouldbebetterifwe...Itisagood/wiseideato...Isupposeitisright...Iwonderif...Whynot...We'dbetter...4HomeworkWriteapersuasivelettertothelocalgovernmenttocontroltheimproperhunts.备课资料1．KillerWhalesCommonname：KillerWhale[来源:学&科&网Z&X&X&K]Scientificname：Orcinusorca[来源:学科网]Size：Femalescanreachlengthsupto24feetandweighbetween3000to8000lb.Malescanreachlengthsupto27feetandcanweighupto12000lb.Calvesareabout8feetlongand300to400poundsatbirth.Wherearetheyfound?[来源:Z_xx_k.Com]FromtheNorthPoletotheSouthPolefromtheIndianOceantotheAtlantic，killerwhalesarefoundinalloceansoftheworld.Whatdotheyeat?3Howdotheygetanamelike“killerwhale”？Killerwhalesareoneofthetoppredatorsinthesea.Asagroup，killerwhalesareknowntoeatfish，squid，seals，sealions，penguins，evenotherwhales.But，keepinmind，itwouldbedifficultforakillerwhaleoffthecoastofCaliforniatoeatapenguin.Killerwhaleseatthefood(orprey)that'savailabletothem.Forexample，akillerwhalethatlivesinthenorthernPacificcanhuntharborseals，Californiasealions，andavarietyoffish.AkillerwhaleintheAntarcticcouldfindWeddellseals，leopardseals，andpenguins!ResearchersstudyingkillerwhalesintheNorthwestPacifichavefoundthatsomepodsfeedprimarilyonfishandothersseemtoprefermarinemammals.Akillerwhaleusesitssharpteethtocatchitsprey.KillerWhaleHighlights：Scientistshavedeterminedthatkillerwhalescanliveamaximumof35years.How？Bylookingatacross－sectionofakillerwhale'stooth.Killerwhales，likeothermarinemammals，produceaperiodicgrowthlayerontheteeth.Bycountingtheselayers，scientistscanestimatetheanimal'sage.Youcantellanadultmalefromanadultfemalebytheshapeoftheirdorsalfin.Thisisamale(photobelow)，howdoweknow？Amale'sfinisverytall(upto6feettall)andtriangularshaped.Afemaleisshorter(3feet)andcurvesbacktowardthedorsalfin(seethepictureofthemother/calfabove)．2．Theearth'soceanscanreachdepthsofupto11000meters.ThatisdeepenoughtocoverMt.Qomolangma！Theoceansareincrediblylargeandcontainseveraldifferenthabitats.Tomakeiteasiertodescribethevariouspartsoftheoceans，marinescientistsusuallydividetheoceansintofivezones.Eachzoneisdifferentmainlyasaresultofhowmuchsunlightreachesit.Mostofthelifeintheoceancanbefoundinthefirstzone，whichbeginsatthesurfaceandgoesdownabout200meters.Becausethereissunlightatthislevel，plantsareabletogrow.Marineanimalssuchasdolphins，sharks，seaturtlesandsealions，andofcourseavarietyoffish，liveinthesunlitpartoftheocean.Itisdifficulttohidefromotheranimalsinthisarea.Thesecondzonestartsat200metersandgoesdowntoabout1000meters.Somesunlightcanreachthislevel，butitisnotenoughforplantstogrow.Becausethiszoneisrelativelydark，manyofthecreaturesthatlivehereareabletomakelightwiththeirbody.Thelightfromtheseanimalsmakest