Unit4AstronomyReadingWarmingUpWhataretheplanetsinoursolarsystem?水星Mercury金星地球火星木星土星天王星海王星VenusEarthMarsJupiterSaturnUranusNeptuneWhatinterestsyouinastronomy?theMilkyWay銀河star恒星planet行星Plutocomet慧星shootingstar/meteor流星blackhole黑洞Haveyoueveraskedyourmother,“Mom,wheredoIcomefrom”?2.Nearlyeverybodyhasthisorthatpuzzles:Howdohumanbeingscomeintobeing?Howdoestheearthcomeintobeing?Pre-readingReadingCanyoupredictthemainideaofthistextbylookingatthetittleHowLifeBeganontheEarth?theoriginofearthReadthepassagecarefullyandanalyseitsstructure.Findoutthekeywordsoftheseparagraphs.Paragraph1:Paragraph2:Paragraph3:Paragraph4:Paragraph5:BigBangatmospherewaterplantsandanimalshumanbeingsthedevelopmentoftheearththedevelopmentoflifeStage1:Thedevelopmentoftheearth(1)AftertheBigBang,whatwastheearthlikeatfirst?

acloudofdust

asolidglobe4.5-3.8billionyearsEarth\(≧▽≦)/explodedwithfireandrock

producedwatervapourandgases(2)Whathappenednext?(3)Thewatervapourandgasesformthe____________.atmosphere(4)Whatappearedastheearthcooleddown?water

Whyiswatersoimportantforthebeginningoflife?

Becausewaterallowedtheearthtodissolveharmfulgasesintooceansandseas.Thisproducedachainreaction,whichmadeitpossibleforlifetodevelop.Stage2:Thedevelopmentoflifesmallplantsappearsinwater1.Whatlifedevelopedafterwaterappeared?Shellfishandallsortsoffish2.Whatlifedevelopedinwaternext?greenplantsbegantogrowonland

insectsappeared3.Whataboutthelifeonland?amphibiansonlandandinthewaterforests4.Whatlifedevelopednextonland?reptilesappeared

dinosaurdeveloped5.Whatlifedevelopedafterforestsappeared?mammalsonland6.Whatlifedevelopedafterdinosaurs?smallcleveranimalssuchashumanbeings7.Whatlifedevelopedaftermammals?1.Insectsandamphibiansappeared.3.Theearthbecameasolidball.5.Reptilesappeared.7.Theearthwasacloudofdust9.Shellfishandotherfishappeared.11.Cleveranimalswithhandsandfeetappeared2.Dinosaursappeared.

4.Smallplantsgrewonthewater.6.Plantsbegantogrowondryland.8.Waterappearedontheearth10.Theuniversebeganwitha“BigBand”.12.Mammalsappeared.831091151741262Canyouputtheorderofdevelopmentoflifeintoatimeline?summaryAfterthe“bigbang”,theearthwasstilljustacloudof_______,it_______loudlywithfireandrock,whichwere_____toproducethe_________,watervapourandothergases.Then________begantoappearedontheearth.dustexplodedintimecarbonwater____________inwaterareconsideredtobetheearliestlivesontheearth.TheO2theysuppliedencouragedthelivesof_______________.Slowlygreenplantsgrewon

land,whichwerefollowedby__________

likeinsects&________.Whentheplantsgrewinto______,______appeared.Then_______developedbutdisappearedlater,whichmadetheriseofatotallydifferentanimal,______