Unit16ScientistsatworkⅠ.TeachingGoals:1.Thinkandtalkaboutscienceandscientists.2.Learnhowtogiveinstructions.3.Studyrulesofwordformation.4.Learntowriteanargumentativeessay.Ⅱ.TeachingTime:FourperiodsⅢ.BackgroundInformation：1.GreatInventions伟大发明Therehavebeenmanygreatinventions,thingsthatchangedthewaywelive.Thefirstgreatinventionwasonethatisstillveryimportanttoday—thewheel.Thismadeiteasiertocarryheavythingsandtotravellongdistances.Forhundredsofyearsafterthat,therewerefewinventionsthathadasmucheffectasthewheel.Thenintheearly1800'stheworldstartedtochange.Therewaslittleunknownlandintheworldpeopledidnothavetoexploremuchanymore.Theybegantoworkinsteadtomakelifebetter.Inthesecondhalfofthe19thcenturymanygreatinventionsweremade.Amongthemwerethecamera,theelectriclightandtheradio.Theseallbecameabigpartofourlifetoday.Thefirstpartofthe20thcenturysawmoregreatinventions:thehelicopterin1909;moveswithsoundin1926;thecomputerin1928;andjetplanesin1930.Thiswasalsoatimewhenanewmaterialwasfirstmade.Nylohcameoutin1935.Itchangedthekindofclothespeoplehadbeenwearing.Themiddlepartofthe20thcenturybroughtnewwaystohelppeoplegetoverdiseases.Theyworkedverywell.Theymadepeoplehealthierandletthemlivelongerlives.Bythe1960'smostpeoplecouldexpecttoliveatleast60.Bythistimemostpeoplehadaverygoodlife.Ofcoursenewinventionscontinuedtobemade.Butmannowhadadesiretoexploreagain.Theworldwasknowntomanbutthestarswerenot.Manbeganlookingforwaystogointospace.Russiamadethefirststep.ThentheUnitedStatestookastep.Sincethenothercountries,includingChinaandJapan,havemadetheirstepsintospace.In1969mantookhisbiggeststepawayfromtheearth.Americansfirstwalkedonthemoon.Thisiscertainlyjustabeginningthought.Newinventionswillsomedayallowustodothingswehaveneverdreamedof.2.TheFirstPlanes最早的飞机Steamengineswerefirsttobetriedinplanes,buttheyweretooheavytobereallyuseful.In1884,suchamachinewasmade,whichconsistedofalargenumberofwingsoneabovetheotherandwasdrivenbyasteamengine.Itissaidthatitroseforamomentofftheground.Anotherrose,butfellandwasdamaged.Therealsuccessofplanesbeganonlywhenpetrolenginewasusedinplanes.OnDecember17,1903,OrvilleWright,anAmerican,flewsafelyinaheavier-than-airmachinefortwelveseconds.HeandhisbrotherWilburhadmadealotofexperimentsandhadtakengreattroubletostudytheartofflyinginglidersbeforetheytriedtoflytheirplanes.Orvillecamedownsafelyafterthefirstshortflight,andonthesamedaytheexperimentwasrepeatedthreetimes.Thelongestoftheseflightslasted59seconds.Thespeedoftheplanewas35milesanhour.Thetwo用心爱心专心brotherswentonwiththeirexperimentsaftertheirfirstsuccess,andin1908WilburgavesomeexhibitionsofflyinginFrance.Allthepeoplewhosawtheexhibitionsweregreatlysurprised.SoonaftertheWrightbrotherssucceededintheirexperiments,othersfollowedintheirfootsteps.LouisBleriot,aFrenchman,flewacrosstheEnglishChannelin1909.Prizesweregivenforflightsfromplacetoanother.Competitionbeganlater.Theplaneimprovedmoreandmorewhenpeoplebegantounderstanditbetter.In1919SirJohn.AlcockandSirArthurBrownmadethefirstflightacrosstheAtlanticOcean,andinthesameyearaplaneflewfromEnglandtoAustralia.Andthen,theageofairtravelarrived.TheFirstPeriodTeachingAims:1.Learnandmasterthefollowingwords:experimentgasflamewheelenginenucleareconomyunnecessarycomfort2.Dosomelistening.3.Dosomespeakingtotalkaboutadvantagesanddisadvantagesofmanysciencediscoveries.TeachingImportantPoints:1.Im...
