中考英语考前阅读理解强化训练
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阅读理解
1.Unlesswespendmoneytospot(认出,发现)andpreventasteroids(小行星)now,onemightcrashintoEarthanddestroylifeasweknowit,saysomescientists.
Asteroidsarebiggerversionsofthemeteoroids(流星体)thatraceacrossthenightsky.MostorbitthesunfarfromEarthanddon'tthreatenus.ButtherearealsothousandsofasteroidswhoseorbitsputthemonacollisioncoursewithEarth.
But$500millionworthofnewtelescopesrightnow,thenspend$10millionayearforthenext25yearstolocatemostofthespacerocks.Bythetimewespotafatalone,thescientistssay,we'llhaveawaytochangeitscourse.
Isitworthit?Twothingsexpertsconsiderwhenjudginganyriskare(i)Howlikelytheeventis;(2)Howbadtheconsequencesiftheeventoccurs.ExpertsthinkanasteroidbigenoughtodestroylotsoflifemightstrikeEarthonceevery500,000years.Soundsprettyrarebutifonedidfall.Itwouldbetheendoftheworld."Ifwedon'ttakecareofthesebidasteroids,they'lltakecareofus,"saysonescientist."it'sthatsimple."
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