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B3U4UsinglanguageListeningtext:THEORIESOFGRAVITYMichaelJonesoftheNewSpaceMagazineistalkingwithspacetravellerLiYanpingaboutchangesinthetheoryofgravity.LY=DrLiYanpingMJ=DrMichaelJonesPart1MJ:HelloDrLiYanping.It’ssogoodofyoutotalktome.Somestudentsaskuswhythingsalways1.__________earthifyou2._______themupintheair.Couldyouexplainit?LY:Wellatfirstpeoplethoughtitwasbecausetheearthwasthe3.________oftheuniverse.Ofcoursethatwaswrong.OnedaylsaacNewtonwatchedanapplefalltotheground.Hesaidthatsomethingelsemustbe4._________theapplebacktoearth.Hecalledit“5._______”.MJ:Isee.Didpeople6.________hisidea?LY:Theydid.Laterthey7.__________thatbiggerobjects(likethesun)havestrongergravitythansmallerobjects(likeourplanets).Ifyou8________________indeepspaceyoucouldn’tfallbacktotheearth.You’rejusttoo9._______.Part2MJ:Doesitmeanthere’snogravity10._________?LY:No.Inaspaceshipyouwouldfeelthepullasit11.____________suchanobject.Youwouldtravelfasterandfastertowardsit.MJ:Untilyou12.___it?LY:Notexactly.Youmay13.______itveryfastandthenitwouldthrowyououtintospaceagain.Afterthatyouwould14._________totheusualspeed.MJ:Howdoyouknowthis?LY:In1905Einsteinsaidthatinspacelargeobjectsmakespace-time15._____;thelargertheobjectthefurtherspace-timebends.Sotimegoes16.______inverystronggravity.MJ:Whatabout17._________?LY:That’saplaceinspacewhichhassuchastrongmassthatnothingcan18.___________itsgravity.Thereisakindofedgearoundthismass.Ifyou19._________thisedgearoundthismassit’simpossibleforyoutogetback.Howeverifyoudon’tcrossthisedgeyoucanstillescape.StephenHawkinghasdonealotof20._________intoblackholes.Hehasshownthatthey“spit”thingsoutaswellas“eat”them.R