英语四级新试题4

英语四级新试题4PartIWriting(30minutes)Directions:Forthispart,youareallowed30minutestowritealettertothepresidentofyouruniversity.Youshouldwriteatleast120wordsbasedontheoutlinegivenbelowinChinese:(注意：此部分试题在答题卡1上。）假设朋友Gary邀请你参加一个聚会，但你因故不能参加，写信向他说明原因，并祝聚会成功。PartⅡReadingComprehension(SkimmingandScanning)(15minutes)（注意：此部分试题请在答题卡1上作答；8-10题在答题卡1上。）SURVIVINGINSPACE1.Everyonewhotravelsinspacesuffersfromfeelingsofmotionsicknessinitially.[A][Y][B][N][C][NG]2.Astronautsarelikelytoincreaseinheightwhileinspace.[A][Y][B][N][C][NG]Motionsicknesstroublesmorethantwo-thirdsofallastronautsuponteachingorbit,evenveterantestpilotswhohaveneverbeenairsick.Thougheveryonerecoversafterafewdaysinspace,bodysystemscontinuetochange.Deprived(丧失)ofgravityinformation,aconfusedbraincreatesvisualillusions.Bodyfluidssurgetochestandhead.Theheartenlargesslightly,asdootherorgans.Sensingtoomuchfluid,thebodybeginstodischargeit,includingcalcium,electrolytes(电解液)andbloodplasma(血浆).Theproductionofredbloodcellsdecreases,renderingastronautsslightlyanemic(贫血的).Withthelossoffluid,legsshrink.Spinal(脊骨的）discsexpand,andsodoestheastronaut-whomaygainfivecentimetersandsufferbackache.Thoughtheprocessmaysoundterrible,astronautsadjusttoit,cometoenjoyitandseemnoworseforwear-atleastforshortmissionssuchasspaceshuttleflightsthatlastaweekortwo.3.It'simportantforastronautstoexerciseinordertokeeptheirmusclesfit.[A][Y][B][N][C][NG]Duringlongerflights,however,physiologyentersanunknownrealm.AsdirectorofRussia'sInstituteforBiomedicalProblemsfrom1968to1988,OlegGazenkowatchedcosmonautsreturnfromlongflightsunabletostandwithoutfainting,needingtobecarriedfromthespacecraft.WearecreaturesoftheEarth,'Gazenkotoldme.Thesechangesarethepriceofatickettospace.Americans,returningfrommonths’longflightsonMir,theRussianspacestation,alsopaidtheprice.Sufferinglossesinweight,musclemassandbonedensity.NASAgeareduptoseehow--evenif-humanswouldsurvivethemostdemandingofspaceventures,amissiontoMars,whichcouldlastuptothreeyears.Wedon'tevenknowifabrokenbonewillhealinspace,saidDanielGoldin,NASA'sadministrator.Togetanswersin1997GoldinestablishedtheNationalSpaceBiomedicalResearchInstitute(NSBRI),apanelofexpertsfromadozenleadinguniversitiesandresearchinstitute.NSBRIwillstudybiomedicalproblemsand,by2010willpresentNASAwithagoornogorecommendationonaMarsmission.JeffreySutton,leaderofthemedicalsystemsteamattheNSBRI,hastreatedtheheadtrauma,wounds,kidneystonesandheartrhythmirregularitiesthatonecouldencounteronthewaytoMars.Onthespacecraftheenvisions,Mars-boundintheyear,say,2018,theremaylurkharmfulbacteriaorcarbonmonoxide.Noproblem.Thedeadlysubstanceswillbedetectedbysmartsensors-microprocessorsnobiggerthanathumbnail-thatwanderatwillthroughthespacecraft,communicatingtheirfindstoacomputerthatwarnsthecrew.Tocopewithinfection,Suttonplansafactorytomakedrugs,evennewones,tocopewithpossibleorganismsonMars.Miniatureopticalandultrasounddeviceswillimagebodyandbrain,whileasmallX-raymachinekeepstrackofanyboneloss.Smartsensorsembeddedinclothingwillmonitoranastronaut'svitalfunctions.Thecrewwillbeabletocraftbodyparts,Suttonsays,preciselytooledtoanastronaut'spersonalanatomyandgenomestoredincomputermemory.Researchersarebuildingartificialliver,boneandcartilage(软骨)tissuerightnow.4.Scientistshavefoundawayofprotectingastronautsfromsolarradiation.[A][Y][B][N][C][NG]LyinginwaitbeyondtheEarth'satmosphere,solarradiationposesadditionalproblems.Thesunflingsbillionsoftonsofelectricallychargedgasintospace,relegatingEarth'svolcaniceruptionstomerehiccups.Nevertheless,NASAofficialsareconfidenttheaccuratemonitoringwillwarnastronautsofsuchevents,allowingthecrewtotakerefugeinanareawherepolyethylene(聚乙稀)shieldingwillabsorbtheradiation.5.Ifastronautsaregiventaskstodo,theyquicklybegintosufferfromstress.[A][Y][B][N][C][NG]Asecondkindofradiation,cosmicraysfromtheMilkyWayorothergalaxies,isamoreseriousthreat-possessingtoomuchenergy,toomuchspeedforshieldingtobeeffective.There'snowayyoucanavoidthem,”saysFrancisCxucinotta,managerofNASA'sJohnsonSpaceCentre.Theypassthroughtissue,strikingcellsandleavingthemunstable,mutilatedordead.Understandingtheirbiologicaleffectsisapriority.Anothermajorconcernisthepsychologicalhealthofastronauts.Andthere'sanewstressoronathree-yearMarsMission-people,othermembersofthecrew.NASAfoundthatthestressesofisolationandconfinementcanbebroughtonrapidlysimplybygivingpeoplefewtasks.MirastronautAndrewThomasdescribedhowsixastronautswereconfinedina12-footsquareroomforaweek.Ifyougivethemlittletodo,stresscanbeachievedinacoupleofdays,saysThomas.6.Scientistsaimtodeveloptechnologythatcanrecognizepsychologicalstates.[A][Y][B][N][C][NG]8.IntheUSeachyear,suddencardiacdeath,causedbyaheart-rhythmdisturbancecalledventricularfibrillationresultsinthedeathsof_________WillNSBRImeetDanielGoldin's2010deadlineforadecisiononMars?Yes,wewillperhapsevenbefore.We'reveryconfident,”saysLaurenceYoung,thedirectorofNABRI.Meanwhile,someofNSBRI'sresearchmaybearfruitonEarth.Theinstitutehasmadeonediscoverythatpromisestosavemanypeopleatriskofsuddencardiacdeath,usuallybroughtonbyaheartrh