Unit21Lesson1ChewingGumTeachingaims:Toreadabouttheeffectsofchewinggum.ToreviseconditionalsTopracticeusingmixedconditionalsTeachingdifficulties:somestudentsmaynotrememberthefirst,secondandthirdconditionalswell.Theformofmixedconditionalsmaybedifficultforsomestudentstomasterandtheymayneedmorepracticewithit.TeachingAids:computerandvideorejectionTeachingprocedures:Step1:lead-in1.Showstudentsadvertisementanvideoaboutgumsoastoraisetheirinterestonchewinggumandmakethemthinkoftheeffectsofchewinggumindailylife.2.Studentsworkinpairsdiscussingthequestionsandrequirethemtosharetheirideaswithclass.Discussinpairsandanswerthefollowingquestions.Whatdoyouthinkofchewinggum?Isitgoodorbadforyou?Doyouoryourfriends/familybuyit?Why?Whatdoyoudoafterchewingit?3.Studentslookatthetitleandpredictwhichissuesmaybecoveredinthearticle.Then,studentsworkindividually,readingthearticlequicklytofindoutwhichoftheirguesseswereright.Step2:readtolearn1.Studentsdividethetextintofourparts,thensummarizethemaintopicofeachpart.Part1(paragraph1---1)IntroductionPart2(paragraph2---4)BenefitsofchewinggumsPart3(paragraph5---7)ThenegativesidesofchewinggumsPart4(paragraph8---8)Betteractivitiesthanchewinggums2.Workindividually,studentstryandfillthetablewiththeinformationtheyrememberfromthefirstreading.Afterfinishingthetable,studentsdiscussitwitheachotherandthencheckanswersasaclass.AdvantageDisadvantageHelpingpeople:1.fightbadbreath2.prevent/stoptoothdecay3.loseweight4.giveupsmoke1.makingdigestionsmoredifficult2.Causingfeelingsofsicknessorheadaches3.Leadingtostomachsickness4.Makingpeopleneglectbrushingtheirteeth3.Studentsworkinpairsansweringthequestions.Askthemtolocatetherelevantpartsinthetextwhichgivetheanswers.1.Howseriousistheproblemofbadbreath?用心爱心专心2.Whatisaddedtosugar-freechewinggumwhichmayhelppreventtoothproblems?3.Accordingtooneresearchproject,whatisonewayofburning70kilocalories?4.Whatwouldbetheeffectonthestomachofconstantchewing?5.Whatotheractivitiesarestatedthatarebetterthanchewinggum?Step3:grammar1.Studentsmatchtheconditionalsentencesinitalicsinthetextwiththefollowingtypes:zeroconditional,1stconditional,2ndconditional,3rdconditional.Checkstudents’answersbyhavingindividualsreadoutthesentencesandthendescribethem.2.Elicitanexamplefromtheclassofeachconditionalform.Step4:consolidationChoosethebestanswer.Step5:Homework:page80,Ex1,4用心爱心专心