Unit4HowLifeBeganontheEarthAQuizGame1.Howoldistheearth?A.About3.5billionyearsB.About4.5billionyearsC.About5.5billionyearsD.About6.5billionyears2.About___oftheearthsurfaceiscoveredbywater.A.20%B.30%C.50%D.70%3.HowmanyplanetsarethereintheSolarSystem?A.6B.7C.8D.94.Whatisthetotalpopulationofhumansontheearth?A.About3.5billionB.About4.5billionC.About5.5billionD.About6.5billion5.Howlongdoestherotation(自转)oftheearthtake?A.12hoursB.24hoursC.amonthD.365days6.OnwhatdayistheEarthdaycelebrated?A.April22B.May4C.August21D.November11MainideaofeachparagraphPara.1Theformation(形成)oftheearth.Para.2Theimportanceofwaterforlife.Para.3Awidelyacceptedtheoryaboutthebeginningsoftheuniverse.Para.4Thearrivalofhumansandtheirinfluenceontheearth.Para.5Thedevelopmentofplantsandanimalsontheearth.Mainideaofthereadingpassage:theearthlifePart1theformationof___________Part2thedevelopmentof_________Detailedinformation1.BigBang2.acloudofdust3.asolidglobe4.explodedwithfireandrock5.producedcarbon,nitrogen,watervapour,othergases----atmospherePart1Howdidtheearthcomeintobeing?6.cooleddown7.waterappeared8.dissolvedharmfulgases&acid—whichmadeitpossibleforlifetodevelopPart2thedevelopmentoflife12345678910extremelysmallplantsinwaterearlyshellfishandallsortsoffishinsectsreptilesamphibiansmammalsdinosaurshumansplantsanimalsgreenplantsonlandforestsListentothereadingpassage.Whilelistening,lookatthepicturesonthescreenwhichcanhelpyouunderstandthetextbetter.BigBangStarsandotherbodiesAcloudofdustaviolentsolidglobeExplodewithfireandrockatmospherewateroceansandseasextremelysmallplantsinwaterearlyshellfishandallsortsoffishgreenplantsonlandinsectsamphibiansforestsreptilesdinosaursdinosaursmammals1.Insectsandamphibiansappeared.3.Theearthbecameasolidball.5.Reptilesappeared.7.Theearthwasacloudofdust9.Shellfishandotherfishappeared.11.Cleveranimalswithhandsandfeetappeared2.Dinosaursappeared.4.Smallplantsgrewonthewater.6.Plantsbegantogrowondryland.8.Waterappearedontheearth10.Theuniversebeganwitha“BigBand”.12.Mammalsappeared.831091151741262Canyouputtheorderofdevelopmentoflifeintoatimeline?Ex.2onP27Sowhetherlifewillcontinueontheearthformillionsofyearstocomewilldependonwhetherthisproblemcanbesolved.Wearemakingtheworldbetter.Wearemakingtheworldworse.DiscussionWhatcanwedototakecareoftheearth?solarenergyplanttreesrecyclerubbishsavewaterpurifyair