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UsinglanguageStep1.LeadinT:Wehavelearntalotaboutastronomy,haveyougotinterestedinit?Ifyouaregoingtostudyastronomy,whatproblemwillyoufacemost?S2:Gravity.T:Whatisgravity?S3:Everythingwillfallbacktotheearthifitisdroppedorthrownaway.Thepulloftheearthiscalledgravity.T:Quiteright.Whofirstgottheideaofgravity?S4:IsaacNewton.T:Howdidhegettheidea?S5:Onedayhewassittingunderthetree.Hesawanapplefall,whichmadehimgettheidea.BesidesNewton,arethereanyotherscientistswhomadeagreatcontributiontotheideaofgravity?S6:AlbertEinstein,StephenHawking.T:Howdideachofthemthinkofgravity?Ordidtheysharethesameideaofgravity?Comeon,thetapewilltellyou.Step2Listening1.Listentothetapeandchoosethebestmainideaofthelisteningpassage(Ex.2P30).Mainidea:①Iheardabouthowthreemenmademistakeswhentheytriedtodescribegravity.②Iheardabouthowthreemenwantedtofindoutaboutthebeginningoftheuniverse.③Iheardabouthowtheideaofgravityhasdevelopedoveralongperiodoftime.④Iheardaboutthreescientistsandtheirwork.Thebestanswer:③2.ListentothetapeagainandfillinthechartinEx.1onP30.(Note:Astronomersandscientiststhinkthatablackholeisaregionofspace(notathing)intowhichmatterhasfallenandfromwhichnothingcanescape—notevenlight.Sowecan’tseeablackhole.Ablackholeexertsastronggravitationalpullandyetithasnomatter.Itisonlyspace-orsowethink.)Step3.ReadingIsaacNewtonAlbertEinsteinStephenHawkingDates1642-17271879-19551942-IdeaEverythingisaffectedbyaforcecalledgravityGravityisconnectedtotimeandspace“Blackholes”“eat”objectsbutalso“spit”themoutOtherinformationItwasonlyabouttheearthItwasabouttheuniverseItwasaboutthingsfoundintheuniversecalled“blackholes”1.FastreadingT:AllthethreegreatscientistsNewton,EinsteinandHawkingplayedanimportantroleinthedevelopmentofideasofgravity.Wouldyouliketoknowmoreaboutgravity?Ss:Yes.T:Isthemoon’sgravitythesameasthatoftheearth?S1:No.T:Readfasttoseehowmanytimeswouldtheforceofgravitychange?S2:Three.2.CarefulreadingT:Whatarethethreetimes?Howwouldtheforceofgravitychange?Andhowdidourweightchange?LeavetheearthVerystrongVeryheavyInspaceDisappearedFloatedweightlesslyOnthemoonVerylightThemasswillbeless3.SummaryT:Good!Iamsureyoumustknowmoreaboutthegravity.Supposeyouareaskedtomakeasummaryaboutthetrip,willyoutry?Youonlyneedtofilltheblacksandthefirstwordhasbeengiven.LastmonthIvisitedthemoonwithmyfriend.Beforeweleft,Iwastoldtheforceofgravitywouldchangethreetimesonourjourney.Thenwetookoff.Aswelefttheearth,Ibecameveryheavy.Graduallytheweightlessened.WhenIwasinspace,itdisappeared.WefloatedweightlesslyinthecabinandIcheeredup.WhenIwasonthemoon,Iwassurprisedtofindoutevenwalkingneedslotsofpracticenowthatgravitychanged.Thereturningoftheearthwasveryfrightening.Wewereamazedtowatchfirebreakoutontheoutsideoftheship.Step4.ReadingtaskT：Great!Butjustimaginethatthemoonhasgreatgravity,thenwhatwillhappen?S3:Itwillpullus.T:Right,maybewhenweareapproachingit,wewillbecaughtinit.Solet’scometotheblackhole.T:Whatareintheblackhole?S:Alargecircleoflightsgoingroundanemptyspace.T:Whatisthecircleoflights?S:Largestars.T:Whatistheemptyspacelike?S:Itlookslikeamouthneedingtobefed.T:Howdidtheyfeel?S:Theywatchedinshockandamazementasalargesunsuddenlydisappearedintothehole.T:Sowhatdidtheydecidetodo?S:Theydecidedtoturnthespaceshipawayfromthehole.T:Whatwashappening?S:notmove---jumpandmovearoundtheedgeoftheoutsideofthehole---pullingusslowlyintoits“mouth”---gofasterandfaster.T:Whatdidtheauthorfeel?S:feelsick,thewatchmovesslowerandslower,mymouthdry,closemyeyes.T:Itseemedthattheywouldbecaughtbythegravityofa“blackhole”.Butwhathappenedlater?S:jumpagain---increaseitsspeed---asfastaslight---flewlikeabird.T:Thistime,howwastheauthoraffected?S:wasbumpedandbanged---abletolookaroundus---thecomputerstartedworkingagain.T:Whatdidtheauthorfeel?S:Exciting.T:Why?S:Theyrealizedthattheyhaddiscoveredsomethingnewabout“blackhole”----They“eat’someobjectsbut“spit”otherobjectsout.Step5.Homework1.Searchformoreabouttheblackhole.2.Readthesetwopassagesagaintofindouthowtoorganizeastory.