专题22 科普类说明文阅读理解 （学生版）2010-2019年近10年高考英语真题分项版汇编

页专题22科普类说明文阅读理解(2010﹒安徽﹒阅读理解B)Haveyoueverwondered?Whydoairplanestakelongertoflywestthaneast?Itcantakefivehourstogowest-eastfromNewYork(NY)toLondonbursevenhourstotraveleast-westfromLondontoNY.Thereasonforthedifferenceisanatmosphericphenomenonknownasthejet(喷射)stream.ThejetstreamisaveryhighaltitudewindwhichalwaysblowsfromthewesttotheeastacrosstheAtlantic.Theplanesmovingataconstantairspeedthusgofasterinthewest-eastdirectionwhentheyaremovingwiththewindthanintheoppositedirection.WhatwouldhappenifthegravityonEarthwassuddenlyturnedoff?Supposingwecouldmagicallyturnoffgravity.Wouldbuildingsandotherstructures(建筑物)floataway?WhathappenedwoulddependonhowstronglythethingswereattachedtotheEarth.TheEarthismovingatquiteaspeed,movingatoverathousandmilesperhours.Ifyouturnsomethingaroundyourheadonastring（细绳）,itgoesaroundinacircleuntilyouletgoofthestring.Thenitfliesoffinastraightline.‘Switchingoff’gravitywouldbelikelettinggoofthestring.ThingsnotattachedtotheEarthwouldflyoffinastraightline.Peopleinbuildingswouldsuddenlyshootupwardsatagreatspeeduntiltheyhittheceiling.Mostthingsoutsidewouldflyoffintospace. 60.Whatinformationcanwegetfromthefirstpassage?A.ItisjetstreamthataffectshowfastairplanesflyB.PlanesgoslowerwhentheyaremovingwiththewindC.IttakesmoretimetoflyfromNYtoLondonthanfromLondontoNYD.TheyetstreamalwaysblowsfromtheeasttothewestacrosstheAtlantic61.Theword”shoot”underlineinthe2ndpassageprobablymeans“”A.sendforB.movequicklyC.comeoutD.grrowquickly62.Itcanbeinferredthatwithoutgravity.A.buildingsandotherstructureswouldfloatawayB.treesandbuildingswouldnoteasilyflyoffC.somethingaroundyourheadwouldnotflyawayD.everythingoutsidebuildingswouldflyoffintospace63.WherecanwemostprobablyreadinthetextA.InareseachpaperB.InashortstoryC.InatravelmagazineD.Inastudent’sbook(2010﹒江苏﹒阅读理解D)Imagine，oneday，gettingoutofbedinBeijingandbeingatyourofficeinShanghaiinonlyacoupleofhours，andthen，afterafulldayofwork，goingbackhometoBeijingandhavingdinnerthere．Soundsunusual，doesn'tit?Butit'snotthatunrealistic，withthedevelopmentofChina’shigh—speedrailwaysystem．Andthat’snota11．Chinahasanevengreaterhigh—speedrailwayplan—toconnectthecountrywithSoutheastAsia，andeventuallyEasternEurope．Chinaisnegotiatingtoextenditsownhigh·-speedrailwaynetworktoupto17countriesin10to15years，eventuallyreachingLondonandSingapore．Chinahasproposedthreesuchprojects．ThefirstwouldpossiblyconnectKunmingwithSingaporeviaVietnamandMalaysia．AnothercouldstartinUrumqiandgothroughKazakhstanandUzbekistan，andpossiblytoGermany．ThethirdwouldstartinthenortheastandgonorththroughRussiaandthenintoWesternEurope．IfChina’splanforthehigh-speedrailwaygoesforward，peoplecouldzipoverfromLondontoBeilinginundertwodays．ThenewsystemwouldstillfollowChina’shigh—speedrailwaystandard．Andthetrainswouldbeabletogo346kilometersanhour，almostasfastassomeairplanes．China’sbullettrain(高速客车)，theoneconnectingWuhantoGuangzhou，alreadyhastheWorld’sfastestaveragespeed．Itcovers1,069kilometersinaboutthreehours．Ofcourse，therearesometechnicalchallengestoovercome．Therearesomanyissuesthatneedtobesettled，suchassafety，railgauge(轨距)，maintenanceofrailwaytracks．So，it’simportanttopayattentiontoeverydetail．Butthekeyissueisreallymoney．Chinaisalreadyspendinghundredsofbillionsofyuanondomesticrailwayexpansion．Chinaprefersthattheothercountriespayinnaturalresourcesratherthanwithcapitalinvestment．ResourcesfromthosecountriescouldstreamintoChinatosustaindevelopment．It’11beawin-winproject.Forothercountries，therailwaynetworkwilldefinitelycreatemoreopportunitiesforbusiness，tourismandsoon，nottomentionthebettercommunicationamongthosecountnes．ForChina，suchaprojectwouldnotonlyconnectitwiththerestofAsiaandbringsomemuch-neededresources，butwouldalsohelpdevelopChina’sfarwest．Weforeseethatinthecomingdecades，millionsofpeoplewillmigratetothewesternregions，wherethelandisemptyandresourcesunused．Withhigh-speedtrains，peoplewillsetupfactoriesandbusinesscentersinthewestonceandfora11．Andthey’11tradewithCentralAsianandEasternEuropeancountries．67．China’snewhigh-speedrailwayplanwillbeawin-winprojectbecause．A．Chinawillgetmuch-neededresourcesanddevelopitswesternregionsB．ChinaandthecountriesinvolvedwillbenefitfromtheprojectinvariouswaysC．ChinawilldevelopitsrailwaysystemandcommunicationwithothercountriesD．theforeigncountriesinvolvedwilldeveloptheirrailwaytransportation，businessandtourism68．Accordingtothepassage，thegreatestchallengetothenewhigh-speedrailwayplanis．A．technicalissuesB．safetyofthesystemC．financialproblemsD．maintenanceofrailwaytracks69．Whichofthefollowingwordsbestdescribestheauthor’sattitudetowardsChina’shigh-speedrailwayplan?A．Critical．B．Reserved．C．DoubtfulD.Positive．70．Whichofthefollowingmightbethebesttitleforthepassage?A．NewRailwayStandardsB．BigRailwayDreamsC．High—speedBulletTrainsD．InternationalRailwayNetwork(2010﹒全国卷Ⅰ﹒阅读理解C)AlongtheriverbanksoftheAmazonandtheOrinocotherelivesabirdthatswimsbeforeitcanfly,flieslikeafatchicken,eatsgreenleaves,hasthestomachofacowandhasclaws(爪)onitswingswhenyoung.Theybuildtheirhomesabout4.6mabovetheriver,animportantfeature(特征)forthesafetyoftheyoung.Itiscalledthehoatzin.Inappearance，thebirdsofbothsexeslookverymuchalikewithbrownonthebackandcreamandredontheunderside.Theheadissmall,withalargesetoffeathersonthetop,brightredeyes,andblueskin.Itsnearestrelativesarethecommonbirds,cuckoos.Itsmoststrikingfeature,though,isonlyfoundintheyoung.Babyhoatzinshaveaclawontheleadingedgeofeachwingandanotherattheendofeachwingtip.Usingthesefourclaws,togetherwiththebeak(喙),theycanclimbaboutinthebushes,lookingverymuchlikeprimitivebirdsmusthavedone.Whentheyounghoatzinshavelearnedtofly,theylosetheirclaws.DuringthedriermonthsbetweenDecemberandMarchhoatzinsflyabouttheforestingroupsof20to30birds,butinApril,whentherainyseasonbegins,theycollecttogetherinsmallerlivingunitsoftwotosevenbirdsforproducingpurposes.63．Whatisthetextmainlyabout?A．Hoatzinsindryandrainyseasons.B．Therelativesandenemiesofhoatzins.C．PrimitivebirdsandhoatzinsoftheAmazon.D．Theappearanceandlivinghabitsofhoatzins.64．Younghoatzinsaredifferentfromtheirparentsinthat．A．theylooklikeyoungcuckoosB．theyhaveclawsonthewingsC．theyeatalotlikeacowD．theyliveonriverbanks65．Whatcanweinferaboutprimitivebirdsfromthetext?A．Theyhadclawstohelpthemclimb.B．Theycouldflylongdistances.C．Theyhadfourwingslikehoatzins.D．Theyhadaheadwithlongfeathersonthetop.66．Whydohoatzinscollecttogetherinsmallergroupswhentherainyseasoncomes?A．Tofindmorefood.B．Toprotectthemselvesbetter.C．Tokeepthemselveswarm.D．Toproducetheiryoung.(2010﹒湖南﹒阅读理解C)PeoplefromEastAsiatendtohavemoredifficultythanthosefromEuropeindistinguishingfacialexpressions—andanewreportpublishedonlineinCurrentBiologyexplainswhy.RachaelJack,UniversityofGlasgowresearcher,saidthatratherthanscanningevenly(均匀的)acrossafaceasWesternersdo,Easternersfixtheirattentionontheeyes."WeshowthatEasternersandWesternerslookatdifferentfacefeaturestoreadfacialexpressions,"Jacksaid."Westernerslookattheeyesandthemouthinequalmeasure,whereasEasternersfavortheeyesandneglect(忽略)themouth."AccordingtoJackandhercolleagues,thediscoveryshowsthathumancommunicationofemotionismorecomplexthanpreviouslybelieved.Asaresult,facialexpressionsthathadbeenconsidereduniversallyrecognizablecannotbeusedtoreliablyconveyemotionincross-culturalsituations.Theresearchersstudiedculturaldifferencesintherecognitionoffacialexpressionsbyrecordingtheeyemovementsof13WesternCaucasianand13EastAsianpeoplewhiletheyobservedpicturesof.expressivefacesandputthemintocategories:happy,sad,surprised,fearful,disgusted,angry,orneutral.Theycomparedhowaccuratelyparticipantsreadthosefacialexpressionsusingtheirparticulareyemovementstrategies.ItturnedoutthatEasternersfocusedmuchgreaterattentionontheeyesandmadesignificantlymoreerrorsthandidWesterners."Theculturaldifferenceineyemovementsthattheyshowisprobablyareflectionofculturaldifferenceinfacialexpressions,"Jacksaid."OurdatasuggestthatwhereasWesternersusethewholefacetoconveyemotion,Easternersusetheeyesmoreandmouthless."Inshort,thedatashowthatfacialexpressionsarenotuniversalsignalsofhumanemotion.Fromhereon,examininghowculturalfactorshavediversifiedthesebasicsocialskillswillhelpourunderstandingofhumanemotion.Otherwise,whenitcomestocommunicatingemotionsacrosscultures,EasternersandWesternerswillfindthemselveslostintranslation.66.ThediscoveryshowsthatWesterners.A.payequalattentiontotheeyesandthemouthB.considerfacialexpressionsuniversallyreliableC.observetheeyesandthemouthindifferentwaysD.havemoredifficultyinrecognizingfacialexpressions 67.Whatwerethepeopleaskedtodointhestudy?A.Tomakeafaceateachother. B.Togettheirfacesimpressive.C.Toclassifysomefacepictures. D.Toobservetheresearchers'faces. 68.Whatdoestheunderlinedword"they"inParagraph6referto?A.Theparticipantsinthestudy.B.Theresearchersofthestudy.C.Theerrorsmadeduringthestudy.D.Thedatacollectedfromthestudy. 69.IncomparisonwithWesterners,Easternersarelikelyto.A.dotranslationmoresuccessfullyB.studythemouthmorefrequentlyC.examinetheeyesmoreattentivelyD.readfacialexpressionsmorecorrectly 70.Whatcanbethebesttitleforthepassage?A.TheEyeastheWindowtotheSoulB.CulturalDifferencesinReadingEmotionsC.EffectiveMethodstoDevelopSocialSkillsD.HowtoIncreaseCross-culturalUnderstanding (2010﹒江西﹒阅读理解D)Moderninventionshavespeededuppeople’slovesamazingly.Motor-carscoverahundredmilesinlittlemorethananhour,aircraftcrosstheworldinsideaday,whilecomputersoperateatlightningspeed.Indeed,thisloveofspeedseemsnever-ending.Everyyearmotor-carsareproducedwhichgoevenfasterandeachnewcomputerboats(吹嘘)ofsavingprecioussecondsinhandlingtasks.Allthissavestime,butataprice.Whenweloseorgainhalfadayinspeedingacrosstheworldinanairplane,ourbodiestellusso.Wegettheuncomfortablefeelingknownasjet-lag;ourbodiesfeelthattheyhavebeenleftbehindonanothertimezone.Again,spendingtoolongatcomputersresultsinpainfulwristsandfingers.Mobilephonesalsohavetheirdangers,accordingtosomescientist;toomuchusemaytransmitharmfulradiationintoourbrains,aconsequencewedonotliketothinkabout.However,whatdowedowiththetimewehavesaved?Certainlynotrelax,orsoitseems.Wearesoaccustomedconstantactivitythatwefinditdifficulttositanddonothingorevenjustonethingatatime.Perhapsthedaysarelonggonewhenwemightlistenquietlytoastoryontheradio,lettingimaginationtakeusintoanotherworld.Therewasatimewhensomepeople’slivesweredevotedsimplytothecultivationofthelandorthecareofcattle.Nomulti-taskingthere;theirliveswentonatamuchgentlerpace,andinafamiliarpattern.Thereismuchthatwemightenvyaboutawayoflifelikethis.Yetbeforewedoso,wemustthinkofthehardtasksourancestorfaced:theyfarmedwithbarehands,oftenlivedclosetohunger,andhadtofashiontoolsfromwoodandstone.Modernmachineryhasfreedpeoplefromthatprimitiveexistence.68.Thenewproductsbecomemoreandmoretime-savingbecause.A.ourloveofspeedseemsnever-endingB.timeislimited.C.thepricesareincreasinglyhigh.D.themanufacturesboastalot.69.Whatdoes“thedays”inParagraph3referto?A.ImaginarylifeB.Simplelifeinthepast.C.TimesofinventionsD.Timeforconstantactivity.70.Whatistheauthor’sattitudetowardsthemoderntechnology?A.CriticalB.Objective.C.Optimistic.D.Negative.71.Whatdoesthepassagemainlydiscuss?A.Thepresentandpasttimes.B.Machineryandhumanbeings.C.Imaginationsandinventions.D.Moderntechnologyanditsinfluence.(2010﹒辽宁﹒阅读理解C)ToomuchTV-watchingcanharmchildren’sabilitytolearnandevenreducetheirchancesofgettingacollegedegree,newstudiessuggestinthelatestefforttoexaminetheeffectsoftelevisiononchildren.Oneofthestudieslookedatnearly400northernCaliforniathird-graders.ThosewithTVsintheirbedroomsscoredabouteightpointsloweronmathandlanguageartsteststhanchildrenwithoutbedroomTVs.Asecondstudy,lookingatnearly1000grown-upsinNewZealand,foundlowereducationlevelsamong26-year–oldswhohadwatchedlotsofTVduringchildhood.Buttheresultsdon’tprovethatTVisthecauseanddon'trideoutthatalreadypoorlymotivatedyoungsters(年轻人）maywatchlotsofTV.TheirstudymeasuredtheTVhabitsof26-year-oldsbetweenages5and15.ThesewithcollegedegreeshadwatchanaverageoflessthantwohoursofTVperweeknightduringchildhood,comparedwithanaverageofmorethan21/2hoursforthosewhohadnoeducationbeyondhighschool.IntheCaliforniastudy,childrenwithTVsintheirroomsbutnocomputerathomescoredthelowestwhilethosewithnobedroomTVbutwhohadhomecomputersscoredthehighest.WhilethisstudydoesnotprovethatbedroomTVsetscausedthelowerscores,itaddstoaccumulatingfindingsthatchildrenshouldn'thaveTVsintheirbedrooms64.AccordingtotheCaliforniastudy,thelow-scoringgroupmight_________.A.havewatchedalotofTVB.notbeinterestedtedinmathC.beunabletogotocollegeD.havehadcomputersintheirbedrooms65.Whatistheresearchers'understandingoftheNewZealandstudyresults?A.Poorlymotivated26-year-oldswatchmoreTV.B.HabitsofTVwatchingreducelearninginterest.C.TVwatchingleadstolowereducationlevelsofthe15-year-olds.D.TheconnectionbetweenTVandeducationlevelsisdifficulttoexplain66.Whatcanwelearnfromthelasttwoparagraphs?A.Moretimeshouldbespentoncomputers.B.ChildrenshouldbeforbiddenfromwatchingTV.C.'IVsetsshouldn'tbeallowedinchildren'sbedrooms,D.Furtherstudiesonhigh-achievingstudentsshouldbedone67.Whatwouldbethebesttitleforthistext?A.ComputersorTelevisionB.EffectsofTelevisiononChildrenC.StudiesonTVandCollegeEducationD.TelevisionandChildren'sLearningHabits(2010﹒山东﹒阅读理解D)Batteriescanpoweranythingfromsmallsensorstolargesystems.Whilescientistsarefindingwaystomakethemsmallerbutevenmorepowerful,problemscanarisewhenthesebatteriesaremuchlargerandheavierthanthedevicesthemselves.UniversityofMissouri(MU)researchersaredevelopinganuclearenergysourcethatissmaller,lighterandmoreefficient.“Toprovideenoughpower,weneedcertainmethodswithhighenergydensity(密度)”，saidJaeKwon,assistantprofessorofelectricalandcomputerengineeringatMU.“Theradioisotope(放射性同位素)batterycanprovidepowerdensitythatismuchhigherthanchemicalbatteries.”Kwonandhisresearchteamhavebeenworkingonbuildingasmallnuclearbattery,presentlythesizeandthicknessofapenny,intendedtopowervariousmicro/nanoelectromechanrealsystems(M/NEMS).Althoughnuclearbatteriescancauseconcerns,Kwonsaidtheyaresafe.“Peopleheartheword‘nuclear’andthinkofsomethingverydangerous,”hesaid,“However,nuclearpowersourceshavealreadybeensafelypoweringavarietyofdevices,suchaspace-makers,spacesatellitesandunderwatersystems.”Hisnewideaisnotonlyinthebattery’ssize,butalsoinitssemiconductor(半导体).Kwon’sbatteryusesaliquidsemiconductorratherthanasolidsemiconductor.“Thekeypartofusingaradioactivebatteryisthatwhenyouharvesttheenergy,partoftheradiationenergycandamagethelatticestructure(晶体结构)ofthesolidsemiconductor,”Kwonsaid,“Byusingaliquidsemiconductor,webelievewecanminimizethatproblem.”TogetherwithJ.DavidRobertson,chemistryprofessorandassociatedirectoroftheMUResearchReactor,Kwonisworkingtobuildandtestthebattery.Inthefuture,theyhopetoincreasethebattery’spower,shrinkitssizeandtrywithvariousothermaterials.Kwonsaidthatbatterycouldbethinnerthanthethicknessofhumanhair.71.WhichofthefollowingistrueofJaeKwon?A.HeteacheschemistryatMU.

B.Hedevelopedachemicalbattery.C.Heisworkingonanuclearenergysource.D.Hemadeabreakthroughincomputerengineering.72.JaeKwongaveexamplesinParagraph4_________.A.toshowchemicalbatteriesarewidelyapplied.B.tointroducenuclearbatteriescanbesafelyused.C.todescribeanuclear-poweredsystem.D.tointroducevariousenergysources.73.Liquidsemiconductorisusedto_________.A.getridoftheradioactivewaste

B.testthepowerofnuclearbatteries.C.decreasethesizeofnuclearbatteriesD.reducethedamagetolatticestructure.74.AccordingtoJaeKwon,hisnuclearbattery_______.A.usesasolidsemiconductor

B.willsoonreplacethepresentones.C.couldbeextremelythin

D.haspassedthefinaltest.75.Thetextismostprobablya________.A.sciencenewsreport

B.bookreview

C.newspaperad

D.sciencefictionstory(2010﹒上海﹒阅读理解C)The2012LondonOlympicshadenoughproblemstoworryabout.Butonemorehasjustbeenadded-acommunicationsblackoutcausedbysolarstorms.AfteraperiodofcalmwithintheSun,scientistshavedetectedthesignsofafleshcycleofsunspotsthatcouldpeakin2012,justintimeforthearrivaloftheOlympictorchinLondon.NowscientistsbelievethatthispeakcouldresultinvastsolarexplosionsthatcouldthrowbillionsoftonsofchargedmattertowardstheEarth,causingstrongsolarstormsthatcouldjamthetelecommunicationssatellitesandinteractlinkssendingfiveOlympicbroadcastfromLondon."TheSun'sactivityhasastronginfluenceontheEarth.TheOlympicscouldbeinthemiddleofthenextsolarmaximumwhichcouldaffectthefunctionsofcommunicationssatellites,"saidProfessorRichardHarrison,headofspacephysicsattheRutherfordAppletonLaboratoryinOxfordshire.Atthepeakofthecycle,violentoutburstscalledcoronalmassejections(日冕物质抛射)occurintheSun'satmosphere,throwingoutgreatquantitiesofelectrically-chargedmatter."Acoronalmassejectioncancarryabilliontonsofsolarmaterialintospaceatoveramillionkilometresperhour.Sucheventscanexposeastronautstoadeadlyamount,candisablesatellites,causepowerfailuresonEarthanddisturbcommunications,"ProfessorHarrisonadded.Theriskisgreatestduringasolarmaximumwhenthereisthegreatestnumberofsunspots.NextweekinAmerica,NASAisscheduledtolaunchasatelliteformonitoringsolaractivitycalledtheSolarDynamicsObservatory(SDO),whichwilltakeimagesoftheSunthatare10timesclearerthanthemostadvancedtelevisionsavailable.TheRutherfordAppletonLaboratoryhelpedtomakethehigh-techcamerasthatwillcaptureimagesofthesolarflares(太阳耀斑)andexplosionsastheyoccur.ProfessorRichardHoldaway,thelab'sdirector,saidthattheSDOshouldbeabletoprovideearlywarningofasolarflareorexplosionbigenoughtoaffectsatellitecommunicationsonEarth"Ifwehaveadvancewarning,we'llbeabletoreducethedamage.Whatyoudon'twantisthingsswitchingoffforaweekwithnoideaofwhat'scausedtheproblem,"hesaid.72.Thephrase"communicationsblackout"inparagraph1mostprobablyreferstoduringthe2012Olympics.A.theextinguishingoftheOlympictorchB.thecollapseofbroadcastingsystemsC.thetransportationbreakdowninLondonD.thedestructionofweathersatellites73.Whatcanbeinferredaboutthesolaractivitydescribedinthepassage?A.ThemostfatalmatterfromthecoronafallsontoEarth.B.Thesolarstormpeakoccursinthemiddleofeachcycle.C.IttakesseveralsecondsforthechargedmattertoreachEarth.D.Thenumberofsunspotsdeclinesaftercoronalmassejections.74.Accordingtothepassage,NASAwilllaunchasatelliteto_________.A.takeimagesofthesolarsystemB.provideearlywarningofthunderstormsC.keeptrackofsolaractivitiesD.improvethecommunicationsonEarth75.Whichofthefollowingmightbethebesttitleofthepassage?A.SolarStorms:AnInvisibleKillerB.SolarStorms:EarthEnvironmentinDangerC.SolarStorms:ThreateningtheHumanRaceD.SolarStorms:HumanActivitiestoBeTroubled(2010﹒浙江﹒阅读理解C)Theterm“multitasking”originallyreferredtoacomputer’sabilitytocarryoutseveraltasksatonetime.Formanypeople,multitaskinghasbecomeawayoflifeandevenakeytosuccess.Infact,someexcellentmentalaerobicexercises(大脑训练)involveengagingthebrainintwoormorechallengingactivitiesatatime.Althoughcheckinge-mailwhiletalkingonaphoneandreadingthenewspapermaybesecondnatureforsomepeople,manytimesmultitaskingcanmakeuslessproductive,ratherthanmore.Andstudiesshowthattoomuchmultitaskingcanleadtoincreasedstress,anxietyandmemoryloss.Inordertomultitask,thebrainusesanareaknownastheprefrontalcortex(前额叶脑皮层).Brianscansofvolunteersperformingmultipletaskstogethershowthatastheyshiftfromtasktotask,thisfrontpartofthebrainactuallytakesamomentofrestbetweentasks.Youmayhaveexperiencedaprefrontalcortex“momentofrest”yourselfifyou’veeverdialed(拨电话)aphonenumberandsuddenlyforgottenwhoyoudialedwhenthelineisanswered.Whatprobablyoccurredisthatbetweenthedialingandtheanswering,yourmindshiftedtoantherthoughtortask,andthentookthat“moment”tocomeback.Researchhasalsoshownthatformanyvolunteers,jobefficiency(效率)declineswhilemultitasking,ascomparedtowhentheyperformonlyonetaskatatime.Multitaskingiseasiestwhenatleastoneofthetasksishabitual,orrequireslittlethought.Mostpeopledon’tfinditdifficulttoeatandreadthenewspaperatthesametime.However,whentwoormoreattention-requiringtasksareattemptedatonetime,peoplesometimesmakemistakes.Weoftendon’trememberthingsaswellwhenwe’retryingtomanageseveraldetailsatthesametime.Withoutmentalfocus,wemaynotpayenoughattentiontonewinformationcomingin,soitnevermakesitintoourmemorystores.Thatisoneofthemainreasonsweforgetpeople’snamesevensometimesrightaftertheyhaveintroducedthemselves.Multitaskingcanalsoaffectourrelationships.Ifsomeonecheckstheire-mailwhileonthephonewithafriend,theymaycomeoffasabsent-mindedordisinterested.Itcanalsocausethatpersontomissoroverlookkeyinformationbeingpassedontothem.49.Whyaresomementalaerobicexercisesdesignedtoengagepeopleinmultitasking?A.Tomakethemmoreproductive.B.Toreducetheirstressandanxiety.C.Todeveloptheircommunicationskills.D.Tohelpthemperformdailytasksmoreeasily.50.AccordingtoParagraph2,whymayapersonsuddenlyforgetwhohascalled?A.Hemayleavehisprefrontalcortextemporarilydamaged.B.Heisprobablyinterruptedbyanothertask.C.Heisprobablynotveryfamiliarwiththepersonhehascalled.D.Hemayneedarestbetweendialingandspeaking.51.Peopletendtomakemistakewhen____.A.theyperformseveralchallengingtasksatatime.B.newmessagesareprocessedoneafteranotherC.theirrelationshipswithothersareaffectedD.thetasksrequirelittlethought52.Whatisthemainideaofthepassage?A.Multitaskinghasbecomeawayoflife.B.Multitaskingoftenleadstoefficiencydecline.C.Multitaskingexercisesneedtobeimproved.D.Multitaskingenablespeopletorememberthingsbetter.(2011﹒陕西﹒阅读理解D)Eversincetheywerefirstputonthemarketintheearly1990s,genticallymondified(GM,转基因)foodshavebeenincreasinglydevelopedandmarketedinmanycountriesintheword,mainlyonthebasisoftheirpromisetoendtheworldwidefoodcrisis.ButcanGMtechnologysolveworldhungerproblems?Evenifitwould,isitthebestsolutiorr?Despitewhatitpromiises,GMtechnologyactuallyhasnotincreasedtheproductionpotentialofanycorp.InfactStudiesshowthatthemostcrownGMcroo.GMsoybeans,hassufferedreducedproductivity.Forinstance,areportthananalysednearlytwodecadesofresearchonmojorGMfoodcropsshowsthatGMengineeringhasfailedtosignificantlyincreaseUScropproduction.Somethingelse,however,hasbeenontherise,WhileGMseedsareexpensive,GMcompanicstellfarmersthattheywillmakegoodprofitsbysavingmoneyonpesticides（杀虫剂）.Onthecontrary,USgovernmentdatashowthatGMcropsintheUShaveproducedanoverallincreaseinpesticideusecomparedtotraditionalcrops.“Thepromisewasthatyoucoulduselesschemicalsandboostproduction.Butnetheristrue,”saidBillChristison,PresidentoftheUSNationalFarmCoalition.Atthesametime,theauthorsofthebookWorldHunger:TwelveMythsarguethatthereactuallyismorethanenoughfoodintheworldandthatthehungercrisisisnotcausedbyproduction,butbyproblemsinfooddistributionandpolitics.Theseindeeddeserveoureffortsandmoney.Meanwhile,theri