period7listeningtask,talkingandwriting teachingaims 1studentswillbeabletofindoutthereasonswhythepopulationofsharksdecreasessharply。 2studentswillbeabletoexpressopinionswiththepoliteexpressionslike: idontthinkitiswiseto。。。 itwouldbebetterifwe。。。 itisagoodideato。。。 isupposeitisright。。。 iwonderif。。。 3studentswillbeabletopersuadethelocalgovernmenttoprotectwildlifeinapoliteway。 teachingprocedures step1beforelistening showstudentsapictureofsharkandtellthemafactthatsharkpopulationsaredecreasingrapidly。 step2duringlistening task1:tellstudentsjordondaviesisinterviewingthesharkexpertdonjamesaboutthesharkssituation。firstreadthestatementsbelow。thenlistenandnumberthesestatementsintheorderthattheyhearthem。 sharkpopulationsgrowataveryslowrate。 alotarekilledbecauseofmodernfishingtechnology。 governmentsshouldtakeactionsothatthefishingofsharksissloweddown。 sharkattacksgetalotofattentioninthenews。 sharkpopulationsaredecreasingataseriousrate。 somespeciesneedtobeprotected。 thechanceofbeingbittenbyasharkisactuallyverysmall。 millionsofsharksarekilledeachyear。 keys:theorder:74815623 task2:listenagainandanswerthefollowingquestions: 1shouldpeoplebeafraidofswimminginthesea? 2howmanypeoplearekilledbysharkseachyear? 3dosharksorpeopleneedtobeprotected?why? 4whyaresomanysharksbeingkilled? 5whydoesthesharksbiologyaffectsharkpopulations?completethesentencesblow。 a:ageforreproducingyoung b:timefortheyoungtodevelop c:numberofyoung 6howlonghavesharkspeciesbeeninexistence? 7whatdoesdonthinkwillhappenifwedontslowdownthefishingofsharks? suggestedanswers: 1no。 2onlyafew。 3sharksneedtobeprotectedasmillionsarekilledeachyearbyhumanbeings,whereasonlyafewhumanbeingsarekilledeachyearbysharks。 4sometimestheyarekilledbyaccidentandsometimesonpurpose。forexample,sharkfinsoupisadelicacyinsomeasiancountries。 515years;14months;79。 6400millionyears。 7donthinksthatmanysharkspecieswillnotbeabletosurvive。 step3postlistening(talking) askstudentstomakeupadialogueaccordingtothesituationbelow。 supposeyouwereacitizeninacoastalcityinchina,sharkhuntisaseriousprobleminyourprovince。trytopersuadethelocalgovernmenttotakeactiontoprotectwildlifeinapolitewaywiththehelpofthefollowingexpressions: idontthinkitiswiseto。。。 itwouldbebetterifwe。。。 itisagoodwiseideato。。。 isupposeitisright。。。 iwonderif。。。 whynot。。。 wedbetter。。。 step4homework writeapersuasivelettertothelocalgovernmenttocontroltheimproperhunts。 备课资料 1killerwhales commonname:killerwhale scientificname:orcinusorca size: femalescanreachlengthsupto24feetandweighbetween3000to8000lb。malescanreachlengthsupto27feetandcanweighupto12000lb。calvesareabout8feetlongand300to400poundsatbirth。 wherearetheyfound? fromthenorthpoletothesouthpolefromtheindianoceantotheatlantic,killerwhalesarefoundinalloceansoftheworld。 whatdotheyeat? howdotheygetanamelikekillerwhale?killerwhalesareoneofthetoppredatorsinthesea。asagroup,killerwhalesareknowntoeatfish,squid,seals,sealions,penguins,evenotherwhales。 but,keepinmind,itwouldbedifficultforakillerwhaleoffthecoastofcaliforniatoeatapenguin。killerwhaleseatthefood(orprey)thatsavailabletothem。forexample,akillerwhalethatlivesinthenorthernpacificcanhuntharborseals,californiasealions,andavarietyoffish。akillerwhaleintheantarcticcouldfindweddellseals,leopardseals,andpenguins! researchersstudyingkillerwhalesinthenorthwestpacifichavefoundthatsomepodsfeedprimarilyonfishandothersseemtoprefermarinemammals。 akillerwhaleusesitssharpteethtocatchitsprey。 killerwhalehighlights: scientistshavedeterminedthatkillerwhalescanliveamaximumof35years。how?bylookingatacrosssectionofakillerwhalestooth。killerwhales,likeothermarinemammals,produceaperiodicgrowthlayerontheteeth。bycountingtheselayers,scientistscanestimatetheanimalsage。 youcantellanadultmalefromanadultfemalebytheshapeoftheirdorsalfin。thisisamale(photobelow),howdoweknow?amalesfinisverytall(upto6feettall)andtriangularshaped。afemaleisshorter(3feet)andcurvesbacktowardthedorsalfin(seethepictureofthemothercalfabove) 2theearthsoceanscanreachdepthsofupto11000meters。thatisdeepenoughtocovermt。qomolangma!theoceansareincrediblylargeandcontainseveraldifferenthabitats。tomakeiteasiertodescribethevariouspartsoftheoceans,marinescientistsusuallypidetheoceansintofivezones。eachzoneisdifferentmainlyasaresultofhowmuchsunlightreachesit。 mostofthelifeintheoceancanbefoundinthefirstzone,whichbeginsatthesurfaceandgoesdownabout200meters。becausethereissunlightatthislevel,plantsareabletogrow。marineanimalssuchasdolphins,sharks,seaturtlesandsealions,andofcourseavarietyoffish,liveinthesunlitpartoftheocean。itisdifficulttohidefromotheranimalsinthisarea。 thesecondzonestartsat200metersandgoesdowntoabout1000meters。somesunlightcanreachthislevel,butitisnotenoughforplantstogrow。becausethiszoneisrelativelydark,manyofthecreaturesthatlivehereareabletomakelightwiththeirbody。thelightfromtheseanimalsmakesthewaterlooklikeaskywithmovingstarsinit。 thethirdzoneoftheoceanisdark。thisplace,about3000metersdeep,maynotseemalikelyhabitat,buttherearemorecreaturesherethanonemightthink。mostoftheanimalsthatlivehereareblackorredbecauseofthelackoflight。 below4000meters,thetemperatureisnearfreezingandthereisnolightatall。infact,thezoneissodarkandemptythatscientistsnamedthiszoneafterthegreekwordfornobottomthereisnotmuchlifetobefoundinthiscoldandunpleasantpartoftheocean,butsomesmallcreaturesstillmanagetosurviveheredespitethehighwaterpressure。 theverydeepestpartoftheoceanisfoundXXmetersfurtherdown。atthisdepth,thewaterpressureisextremelyhighandlifeisverydifficultforthefewcreaturesthatlivehere。comparedtotheotherzones,thisonehasverylittlelife。sincethereisnolighthere,someoftheanimalsdonothaveeyes。 nexttimeyoulookattheoceanfromthebeachoronamap,rememberthatwhatyouareseeingisonlythesurfaceonlythebeginningofthelargeandvariedadventure。