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1、Exchangeaglancewithsomeone1.everyglance2.toavoid3.ceasingto4.Uneasy5.theroleof.GeraldoRivera6.TVprogram7.Five8.alloftheabove9.anorganizationin10.RiveraneverIntheolddays,11.usuallywitnessed12.tolearn13.learninghow14.hisdesire15.dyingpatientsshouldTheoldesta
2、ndsimplestmethod16.personality17.hadapleasant18.peoplewith19.areoften20.differentopinionsPassage5Spaceisadangerousplace,notonlybecauseofmeteors(流星)butalsobecauseofraysfromthesunandotherstars.Theatmosphereagainactsasourprotectiveblanketonearth.Lightgetsthro
3、ugh,andthisisessentialforplantstomakethefoodwhichweeat.Heat,too,makesourenvironmentendurable.Variouskindsofrayscomethroughtheairfromouterspace,butenormousquantitiesofradiationfromthesunarescreenedoff.Assoonasmenleavetheatmospheretheyareexposedtothisradiati
4、onbuttheirspacesuitsorthewallsoftheirspacecraft,iftheyareinside,dopreventalotofradiationdamage.Radiationisthegreatestknowndangertoexplorersinspace.Theunitofradiationiscalled"rem".Scientistshavereasontothinkthatamancanputupwithfarmoreradiationthan0.1remwith
5、outbeingdamaged;thefigureof60remshasbeenagreedon.Thetroubleisthatitisextremelydifficulttobesureaboutradiationdamage--apersonmayfeelperfectlywell,butthecellsofhisorhersexorgansmaybedamaged,andthiswillnotbediscovereduntilthebirthofdeformed(畸形的)childrenoreven
6、grandchildren.MissionsoftheApolloflightshavehadtocrossbeltsofhighradiationand,duringtheoutwardandreturnjourneys,theApollocrewaccumulatedalargeamountofrems.Sofar,nodangerousamountsofradiationhavebeenreported,buttheApollomissionshavebeenquiteshort.Wesimplydo
7、notknowyethowmenaregoingtogetonwhentheyspendweeksandmonthsoutsidetheprotectionoftheatmosphere,workinginaspacelaboratory.Drugsmighthelptodecreasethedamagedonebyradiation,butnoreallyeffectiveoneshavebeenfoundsofar.21.Accordingtothefirstparagraph,theatmospher
8、eisessentialtomaninthat___.A)itprotectshimagainsttheharmfulraysfromspaceB)itprovidessufficientlightforplantgrowthC)itsuppliestheheatnecessaryforhumansurvivalD)itscreensoffthefallingmeteors22.Weknowfromthepass
