Unit+5+A+delicate+World+Listening+and+speaking 高二英語(yǔ)外研版（2019）選擇性必修第二冊(cè)

Unit5Period3ListeningandSpeaking新課導(dǎo)入What'syourunderstandingofthefoodchain?課堂學(xué)習(xí)1Lookatthediagramandanswerthequestions.Payattentiontothewordsandexpressionsinbold.1Whatdoesthediagramshow?2Whataretherelationshipsbetweenthelivingthings?1Whatdoesthediagramshow?Thediagramshowsafoodchain-theconnectionbetweenthelivingthings.2Whataretherelationshipsbetweenthelivingthings?Thelivingthingsarecloselyconnectedwitheachotherbythefoodtheyeat.Secondaryconsumerspreyonprimaryconsumers,primaryconsumersfeedonproducers,andproducersabsorblightfromthesun,andwateranddissolvednutrientsfromthesoil,whichareprovidedbydecomposers.2Completethepassagewiththecorrectformofthewordsandexpressions.absorb,dissolvednutrients,relyon,provideenergy,feedon,preyon,breakdown,releasedInawoodlandecosystem,treesandotherplantsareproducers.They

1____________waterandtakeinnutrientsfromthesoilandenergyfromthesun.

Insectsareanexampleofaprimaryconsumer.They2____________theproducerstoprovidefoodforthem,andare3____________bysecondaryconsumers:smallmammalsandbirds.They4____________theprimaryconsumers.Worms,fungiandbacteriaaredecomposers.They5____________animalwasteandtheremainsoflivingthings.Thechemicalsthesedecomposers6____________fertilisethesoilandgivetheplantsthenutrientstheyneedtogrow.absorbrelyonfedonpreyonbreakdownrelease?Oneoftheoldestspeciesintheecosystem,thehoneybeehasbeeninexistenceformillionsofyears.?Ahoneybeecanflyasfastas24kilometresperhouranditswingscanbeat200timespersecond.?Injustonejourneytocollectpollenandnectar,onesinglehoneybeecanpollinateasmanyas50to100flowers.DidYouKnow?3Listentotheconversationandchoosethetruestatements.1.Beesareveryimportanttoourfoodsupplybecausetheyprovidehoney.2.Thebeepopulationisdeclining.3.Withoutbees,humanswoulddieout.4.Allhumancropsdependonbeesforpollination.5.Ifbeesbecameextinct,otherinsectscouldpollinateenoughcrops.6.Humansareresponsibleforthedeclineinthebeepopulation.4Listenagainandcompletetheflowchart.Acombinationofthingsdamagesbeehabitats,mainly1_____________.Thebeepopulationis2_____________.Accordingtostatistics,beenumbersintheUS3_____________injustoneyear.Withoutbees,cropswould4_____________.5_____________wouldnotbeabletocompensateforthelossofbees,because6_____________ofthespeciesofcrops.Animalsthatliveonthecrops7_____________.Humanshavenothingtoeatanddieout.↓Answers:

1.pesticidesandclimatechange2.decliningveryquickly3.havefallenby17%4.beunabletoreproduce5.Otherinsects6.beesareresponsibleforpollinatingabout70%7.woulddieout5Completetheboxeswiththeexpressionsfromtheconversation.?Youmustbekidding!?Idon'tbelieveit!?It'safact!?Don'tforgetthat...?Areyousureabout...??Checkitoutforyourself...

?Accordingtostatistics...RespondingtodoubtExpressingdoubt?Youmustbekidding!?Idon'tbelieveit!?Areyousureabout...??It'safact!?Don'tforgetthat...?Checkitoutforyourself...?Accordingtostatistics...6Workinpairs.Talkaboutwhatwouldhappentotheecosystemifanotherspeciesdiedout.Usethewordsandexpressionsinthissection.Nowthinkabouthowyourknowledgehelpedyoucontributetothediscussion.Example:Developing:Icanusesomeusefulwordsandexpressions,andgivesomeroughideasduringthediscussion.Satisfactory:Icanusecorrectwords,expressionsandcompletesentencestoclearlyshowmyideasduringthediscussion.Exemplary:Icanuseaclearstructurewithproperwordsand