人教版（2023）必修 第三冊Unit 4 Space Exploration單元精練完形填空 練習(xí)（含解析）

第第頁人教版（2023）必修第三冊Unit4SpaceExploration單元精練完形填空練習(xí)（含解析）Unit4完形填空練習(xí)-2023-2024學(xué)年高中英語必修第三冊單元精練（人教版2023）

一、完形填空

Beinganastronautsoundscool,doesn’titInspace,theygettodosomeprettyamazingthings,like1inzerogravity.However,without2,therearealsoplentyofthingsastronautscan’tdo,andthat’svery3.What’sworse,theycan’tevenlettheirsadnessshow—becauseit’simpossibleto4inzerogravity.

Ofcourse,astronautscanstillproducetears.Butcryingismuchmoredifficultinspace.Becauseoftheir5environment,tearsdon’tflowdownwardoutoftheeyes.This6thatwhenyoucryinspace,yourtearshavenowheretogo—theyjust7there.InMay2023,astronautAndrewJ.Feustel8thisduringoneofhisspacewalks.

Besidesmakingyour9unclear,thiscanalsocausephysicalpain.BackonEarth,tearsaresupposedtobring10totheeyes.Butthat’snotthecaseinspace.“Myrighteyeispainfullikecrazy,”Feusteltoldhisteammateduringthewalk.

Sincegravitydoesn’tworkinspace,astronautsneedsomeextrahelptogetridofthetears.Feustel11torub(擦)hiseyesagainsthishelmettowipethetearsaway.Anotherchoiceistojustwait.“Whenthetearsgetbigenoughthey12breakfreeoftheeyeandfloataround,”astronautRonParisesaid.

Inspace,astronautscan’teatordrinkin13ways.Norcantheytalktoeachotherdirectly.Theycan’tevenburp(打嗝),becausethereisnogravitytoholdthefood14intheirstomach.Iftheydoburp,theyjust15throwingupeverythingintheirstomach.Thus,perhapsit’sonlyspaceexplorerswhocanhonestlysay,“Gravity,you’rethebest.”

1．A．leapingB．floatingC．eatingD．talking

2．A．gravityB．doubtC．a(chǎn)idD．effort

3．A．riskyB．lifelikeC．sadD．unfortunate

4．A．foreseeB．viewC．prayD．cry

5．A．dangerousB．extremeC．stableD．weightless

6．A．expectsB．meansC．demandsD．shows

7．A．meetB．developC．stayD．leave

8．A．witnessedB．a(chǎn)cknowledgedC．experiencedD．suffered

9．A．mindB．visionC．senseD．idea

10．A．peaceB．disasterC．stressD．comfort

11．A．choseB．decidedC．stoppedD．hesitated

12．A．fluentlyB．exactlyC．efficientlyD．simply

13．A．regularB．normalC．particularD．rational

14．A．outB．offC．downD．up

15．A．giveupB．endupC．putoffD．feellike

Humansaren’ttheonlylifeformsontheInternationalSpaceStation.They16theirworkandlivingspacewithplants.

Infact,asspacetripsbecome17itwillbenecessarytogrowfoodinspace.Anine-monthtriptoMarswould18hugeamountsoffoodandwater.The19oftakinganythingintospaceisabout$22,000perkilogram.20this,it’snotpracticaltosendeverythingneededforsuchalongjourney,onlytobe21onceandthrownaway.

Thisiswhygrowingplantsinspacewillbeso22.Plantscanservemanyusesonalongspacejourney.Theyarearenewable23source.Astronautswill24theadditionoffreshfruitsandvegetablestotheirdietofdryfoods.Also,becauseplantsusecarbondioxideandproduceoxygen,theycanhelp25airqualityinsidethespaceship.Atpresent,alloxygenistakenaboardinhugecontainersandthencaughtagain26itcanbereused.

However,thereis27ingrowingplantsinspace.Becauseofthelackofgravityinspace,theoxygenthattheplantsproducestaysaroundtheplants.Thiscankillthem,sofansare28tocirculatetheair.Withoutgravity,rootsdon’t“know”togrowdownandleavesdon’t29togrowup.Specializedcontainersarebeingdevelopedtohelptheplantsgrow30.Thereareproblemswithsoilaswell.Assoilistoo31tosendtospace,specialliquidgels(凝膠)areusedtosupportplantgrowth.These32waterandsendittotheplants.

Scientistsarealso33theplantsthemselves.Theyaretryingtobreed(培育)plantstogrowmorequicklyandtogrowwithlesswaterandlight.Theyarealsolookingfor34tomakeplantsmoreresistant(抵抗的)todisease.35,suchnewwaysinplantbreedingcouldresultinimprovementsbackhereonEarth.

16．A．shelterB．blockC．exchangeD．share

17．A．longerB．cheaperC．easierD．safer

18．A．produceB．wasteC．storeD．require

19．A．costB．dangerC．numberD．chance

20．A．AccordingtoB．ApartfromC．BecauseofD．Insteadof

21．A．seenB．usedC．movedD．fixed

22．A．hardB．importantC．strangeD．modern

23．A．waterB．medicineC．foodD．money

24．A．forgetB．imagineC．noticeD．welcome

25．A．improveB．forecastC．recordD．monitor

26．A．tillB．soC．thoughD．unless

27．A．funB．pointC．difficultyD．purpose

28．A．boughtB．broughtC．neededD．made

29．A．knowB．likeC．learnD．a(chǎn)gree

30．A．a(chǎn)ccidentallyB．correctlyC．freelyD．suddenly

31．A．richB．dryC．muchD．heavy

32．A．preferB．containC．controlD．drink

33．A．sufferingfromB．waitingforC．givingupD．workingon

34．A．waysB．placesC．jobsD．signs

35．A．DisappointedlyB．UnfortunatelyC．HopefullyD．Interestingly

WhichisthemostfamoussheepintheworldAsheepcalledDolly.ButwhyisDolly36

Thatisbecauseunlikeothersheep,Dollywasnot37intheusualmanner.Sheisactuallya38ofhermother,likeanidenticaltwin.

Weallhavefathersandmothers.Infact,alltheanimalsweknowofhavethemtoo.Aclone,39,doesnotneedtohaveboththeparents.

Ourbodyismadeupofcellswhichhaveinformationto40theirworkintheformofDNA．Thisiscalledthegeneticcode.Everyorganismgetshalfofthis41fromthefatherandtheotherhalffromthemother.

Weallhavegrownfromasinglecellwhich42thesetwopartsoftheDNA．It43millionsoftimestogiverisetomillionsofcellswhichformourbody.Andeachcellhasacopyofallthegeneticinformationneededbythe44.Thismeansthateachcellofourbodyhasenoughinformationto45otherhumanbeingslikeus.

Inthe46ofcloning,thescientistsextract（提?。﹖heDNAfromananimalcellandimplantitintoaneggcelltakenfromanotheranimal.Before47it,theDNAoftherecipient’scellis48.

ThisishowDolly’s49began—fromasinglecelltakenfromtheudderofhermother.TheDNAinhermother’scellwasremovedand50intotheeggcellofanothersheep.Afewmonthslater,Dollywasbornandremaineda51lamb,acloneofhermother—52abiologicalfather.

Itis53possibletoclonehumansaswell.Wemighthaveclonesofsupermodelsandgreatscientists.WhatifsomeonecreatesacloneofHitlerSinceitis54,someone,somewheremusthaveattempteditalready.

55wehavelearntfromthestoryofJurassicPark,wemightlosecontroloverthesituationafterapoint.Isthereadisasterwaitingtohappen

36．A．famousB．gentleC．wildD．small

37．A．keptB．bornC．fedD．raised

38．A．childB．modelC．copyD．partner

39．A．howeverB．thereforeC．thusD．so

40．A．sendawayB．goaboutC．takeoverD．findout

41．A．geneB．formC．workD．information

42．A．reflectsB．a(chǎn)ffectsC．containsD．develops

43．A．dividesB．explodesC．growsD．moves

44．A．bloodB．bodyC．fleshD．hair

45．A．treatB．offerC．provideD．create

46．A．endB．theoryC．processD．plan

47．A．implantingB．experimentingC．examiningD．a(chǎn)nalyzing

48．A．calculatedB．removedC．recordedD．marked

49．A．a(chǎn)dventureB．journeyC．a(chǎn)ssumptionD．life

50．A．pouredB．rolledC．broughtD．slipped

51．A．braveB．healthyC．livingD．cruel

52．A．forB．ofC．fromD．without

53．A．technologicallyB．commerciallyC．economicallyD．mentally

54．A．complicatedB．possibleC．straightforwardD．legal

55．A．AsB．IfC．ThoughD．Till

Irmastartedabusiness,butlaterforlackofmoney,hehadtocloseit.Afterthathestartedtofeelvery56.

ThisproblemofIrmawaslater57byProfessorKrishnan.Onedayhe58Irmatohishomeandasked,“Areyoustillannoyed”“Yes,allmyeffortshavebeen59,”Irmaanswered.Hearingthis,theprofessor60himadeadtomatoplantandsaid,“Itookcareofitcarefully,61itstilldied.Thereisalwayssomething62thathappens.”“Ifsuccessisonlyamatterofluck,whatisthe63ofdoingsomuch”askedIrma.“Youwillunderstandafteryouopenthatdoor,”saidtheprofessor.Irmaopenedit,andsawlotsof64andhealthytomatoplantsthere.“Oh!Howdidyoudothat”askedIrma.

“Ofcourse,notallmyeffortshavebeenwasted;soitiswithyours.Ifyou65doingtherightthings,thenyour66ofsuccessaregreatlyincreased.Butifyoufeeldefeatedbecauseoffailure,lifewon’tgiveyouany67.”Atlast,Irmaunderstoodthelessonofsuccess,68whattodoandcameoutwithrenewed69.Finallyhehadaverybigbusiness.

Itistruethatnomatterwhatwetry,wecan’t70theresult,butit’salsotruethatthose,whonevergiveup,achievesuccessintheend.

56．A．scaredB．depressedC．shockedD．determined

57．A．discoveredB．a(chǎn)nalyzedC．valuedD．complained

58．A．wishedB．encouragedC．invitedD．permitted

59．A．recognizedB．wastedC．savedD．ignored

60．A．mailedB．returnedC．showedD．indicated

61．A．butB．soC．orD．a(chǎn)nd

62．A．unusualB．unbalancedC．unforgettableD．unexpected

63．A．importanceB．challengeC．a(chǎn)dvantageD．theory

64．A．strongB．newC．weakD．regular

65．A．a(chǎn)voidB．considerC．keepD．enjoy

66．A．timesB．chancesC．featuresD．experiences

67．A．rewardB．joyC．moneyD．harvest

68．A．pointedoutB．figuredoutC．leftoutD．gaveout

69．A．strengthB．a(chǎn)ttentionC．interestD．energy

70．A．replaceB．monitorC．controlD．move

InSeptember2023,sixpeoplecameoutfromasmallsolar-poweredbuildingonthesideofavolcanoinHawaii.Theywere71ofasimulated(模擬的)missiontoMars,andtheyhadbeenlivinginthebuildingfornearlyoneyear,72fromtherestoftheworld.

ThismissiontoMarswaspartofanongoing73toseehowpeoplewoulddealwiththechallengesoflivingonanotherplanet.Basedonthe74oftheexperimentsofar,herearefourabilitiesyouwouldneedto75onMars.

ThefirstisResourcefulness(足智多謀).Whenthewatersystembroke,thegrouphadtwo76.Theycouldfigureouthowtofixitortheycould77monthsforsuppliestobedeliveredfrom“Earth”—bywhichpointtheywouldbedead.Sothey78itthemselves.

ThesecondisImagination.Thegroupmembershavesaidboredomwasamajor79.OnMars,youwouldn’thaveNetflixorXbox,soyou’dhaveto80otherformsofentertainment(娛樂活動).

ThethirdisTolerance(寬容).Thebuildingisonlyaquarterofthesizeofabasketballcourt.Ifyou’re81annoyedbypeople,lifeonMarsmightnotbeforyou.Whethereating,working,exercising,orrelaxing,youwouldhardlybe82.

ThelastisIndependence.Duringamission,thereisnoreal-time83betweenthegroupandanyoneon“Earth.”Theyhaveemail,84messagesareona20-minutedelay(延遲),simulatinghowlongitwouldtakemessagesto85betweenEarthandMars.SoyouwouldberemovedfromthelivesofyourlovedonesbackonEarth.

71．A．captainsB．membersC．a(chǎn)stronautsD．directors

72．A．pulledB．keptfreeC．protectedD．cutoff

73．A．explanationB．holidayC．experimentD．game

74．A．resultsB．originsC．wishesD．requirements

75．A．refuseB．copyC．a(chǎn)rgueD．survive

76．A．tasksB．choicesC．dreamsD．conditions

77．A．spreadB．prepareC．waitD．leave

78．A．fixedB．wateredC．calledD．planted

79．A．desireB．habitC．a(chǎn)bilityD．challenge

80．A．limitB．forgetC．findD．leap

81．A．hardlyB．easilyC．secretlyD．suddenly

82．A．a(chǎn)loneB．politeC．successfulD．normal

83．A．communicationB．systemC．teachingD．meeting

84．A．soB．butC．ifD．unless

85．A．escapeB．walkC．travelD．change

Aquaculture—orseafarming,asitissometimescalled—isoneofthebrightesthopesforfindingananswertotheproblemofaworldfoodshortage.Althoughitmaybeyearsbeforeseafarmingproduceslargequantitiesoffood,itisalreadypartiallysuccessful.Oneofitssuccessesisthegrowingofoyster(牡蠣).

OysterfarmingisabignewbusinessonCapeCod,wherelargecropsofoystershavebeenharvested.Thewaterstherewerefamousfordeliciousoystersuntilthesupplygaveoutaboutfifteenyearsago.“There’sawholegenerationofpeoplewhohavenevereatenoysters,”saidKarlTouraine,marketingdirectorofAquaDynamicsCorporation,acompanythatgrowsoystersonnylonstrings(尼龍繩)hangingfrommetalframes(金屬架).“Forabouttwentyyearstheoysterhasbeeninshortsupply,andouraimistochangethisbyusingnew,moderngrowingtechniques,”heexplained.

“Wareham,onCapeCod,isthefirstplaceintheUSwhereoystersarebeinggrownonframesjustoffthebottomofthesea,”saidHankMcAvoyoftheNationalMarineFisheriesServiceinGloucester.“Butthere’snothingnewaboutoff-bottomraising,”Mr.McAvoyadds.“It’sbeendonesuccessfullyinNorwayandAustraliaand,inthelastfewyears,inSpain.TheJapanesehaveusedthisformofseafarmingforyears,andthey’rethemostsuccessful,withayearlycropofmorethan46,000poundsofshelledoystersanacre.”

TheAquaDynamicsgroupgrowsoystersonstrings,awayfromthebottomsothattheoysters’naturalenemiescannotreachthem.“Whenanoysteravoidenemiesandliveinunpollutedwaterwithplentytoeat,he’llgrowfast.”KarlTouraineexplains.“Oysterswillattachthemselvestoalmostanythingtheycan,”hecontinues.“AtWareham,weuseshellswhichwetiewithnylonstringshangingfrommetalframes.Welowerthestringsintothewater,leavingatleastafootofwaterbetweenthelowestshellandthebottom.”

“Sofarthegrowthhasbeenexcellentandthetasteisjustdelightful,”Mr.Tourainenoteshappily.

86．What’sthepurposeofParagraph1

A．Toshowtheimportanceoffarming.

B．Tointroducethetopicofoysterfarming.

C．Togiveabriefintroductiontoaquaculture.

D．Toencouragepeopletosavefood.

87．Wecanlearnfromthetextthatoff-bottomraising________.

A．isabrandnewwayinNorway.

B．hasfailedtospreadinSpain.

C．ispopularinmanyplaces

D．resultsinlowproductioninJapan.

88．Whatistheadvantageofoff-bottomoysterfarming

A．Itcanimproveoysters’taste.

B．Itoffersoystersanenemy-freeenvironment.

C．Itgreatlyreduceswaterconsumption.

D．Ithelpscontrolenvironmentalpollution.

89．WhatisKarlTouraine’sattitudetowardsoff-bottomraising

A．Approving.B．Worried.C．Unconcerned.D．Unclear.

Theideaofholidaystothemoonwasonceaconceptofsciencefiction.However,severalcompaniesareracingtomakeita90.Topreparefortheseholidays,HorizonStudioshas91theworld’sfirstluggageforspacetravel.

Thesuitcasewasco-designedbyAlyssaCarson,whowantedtobeoneofthe92onboardNASA’sfirstmannedmissiononMarsin2033.

Thesuitcase,calledHorizonONE,isbuiltfromaspecialmaterial,makingitverystrongand93.Itisestimatedthatthecaseweighsnomorethan900grams!

Thebaseofthebagiselectromagnetic(電磁的),94ittoguidetothefloororwallseveninzero95environments.Meanwhile,thesuitcaseis96withalotofelectronics,includingGraphenesupercapacitors(石墨烯超級電容器)andachargingfieldforwirelesscharging,anin-builtsmartscreen,andfingerprint97.However,thesuitcasehasaneye-wateringpricethatislikelyto98manycustomers.Itiscurrentlypricedat$40,000.

StefanHolwe,founderofHorizonStudios,said,“Asa99travelbrand,itisourjobtoenable100mindstogofurther,sothisprojectliesveryclosetoourhearts.WearehappytoworkwithAlyssa,who101representsspacetravelforthenextgeneration.”

Spaceisseenasthefinalfrontier,andHorizonONEbringsusonestepcloser.Itshowshowfarsmarttraveltechnologyhascome,andhowfaritcan102.

Sadly,thesuitcaseisstilla103andHorizonStudioexpectsthefirstspacerangeto104in2030.

90．A．dreamB．realityC．hopeD．success

91．A．producedB．releasedC．demonstratedD．revealed

92．A．designersB．scientistsC．pilotsD．a(chǎn)stronauts

93．A．smallB．lightC．largeD．heavy

94．A．a(chǎn)llowingB．causingC．forcingD．forbidding

95．A．toleranceB．a(chǎn)ctivityC．gravityD．interaction

96．A．equippedB．burdenedC．confrontedD．surrounded

97．A．installmentB．recognitionC．facilityD．instrument

98．A．giveoffB．turnoffC．putoffD．putaway

99．A．traditionalB．newC．fashionableD．smart

100．A．curiousB．dangerousC．consciousD．a(chǎn)nxious

101．A．hopelesslyB．a(chǎn)imlesslyC．carelesslyD．fearlessly

102．A．runB．goC．travelD．stand

103．A．brandB．projectC．conceptD．designer

104．A．departB．launchC．a(chǎn)rriveD．disappear

Allpassengersboarded(登機),andtheflightwouldbeontime.However,Inoticedanadultpassengersittingatthegate(登機口)crying.Iaskedthegatestaffwhatwasupandtheytoldmethepassengerwasnot105toboardduetoaproblemofhisticket.Hislastnameintheticketwas106wronglybyaletterbuthehad107itbefore.

Themantoldmethathisfatherwasjustinthe108andheneededtotakethisflighttohopefullyseehimbeforehe109.Unfortunately,therewasnothingthegatestaffcoulddoaboutit.Theytoldhimtobuyanewticket.110,theflightwastoleavetenminuteslateranditwasimpossibleforhimtodoso.Hetoldmehewouldbereally111ifhewouldntbeabletosayhisfinalgoodbyetohisdad.Seeingagrownmancryingsadly,Iwassurethathewastellingthe112.

Iconsideredforawhileandthenthoughtof113Icoulddotohelphim.Asamemberofthestaff,Ihavea114-Icanissue(發(fā))ticketsthroughanonlinesystemtomyfamilyor115.Then,Iprovidedastaffticketforthispassenger.Ipassedthetickettohim116hisknowingwhatIddone.Ijusthopedthathewouldnt117anyofhisfatherslastwords.Later,thegatestafftoldmetheywouldhelpmekeepthe118aswecanonlyusethestaffticketsforpeopleweknow.

Iwassoproudthatday119Ididsomethingmeaningfulforapersoninneed.

105．A．forcedB．a(chǎn)llowedC．a(chǎn)dvisedD．persuaded

106．A．readB．spelledC．understoodD．remembered

107．A．foundB．recordedC．imaginedD．ignored

108．A．a(chǎn)irportB．officeC．schoolD．hospital

109．A．gaveupB．camebackC．passedawayD．settleddown

110．A．InsteadB．HoweverC．OtherwiseD．Therefore

111．A．regretfulB．confusedC．a(chǎn)nxiousD．hopeless

112．A．lieB．truthC．jokeD．story

113．A．nothingB．a(chǎn)nythingC．somethingD．everything

114．A．goalB．dutyC．taskD．right

115．A．petsB．friendsC．customersD．passengers

116．A．forB．a(chǎn)fterC．sinceD．without

117．A．missB．repeatC．forgetD．mind

118．A．secretB．ruleC．promiseD．a(chǎn)ppointment

119．A．becauseB．beforeC．untilD．unless

Whetherit’sfromanawfulbreakuporapainfullifeevent,somememoriescanreturnrepeatedlytoourmindfortheentirelives.But,whatifsciencecan120yourbadmemoriessothatyoucanstartalloveragainAsisknowntoall,memoryisanincrediblycomplex121.Whilescientistsusedtobelieveitwaslikeafilingcabinetandparticularmemorieswerestoredindifferentsectionsofthebrain,wenowknowthisis122.

Infact,eachmemoryisabrainwideprocess.Ifyouenduprememberingsomething,it’sbecausethecellsinyourbrainarebeingfired,123newconnectionsandlinksandliterallyrebuildthecircuitryofyourmind.Andthischangeispartially124byproteinsinthebrain.Sowhatiftheproteinsaren’tavailable

Simplyput,memoriescan’tbemade.Seriously,scientistshavetestedthisbygivinganimalsdrugsthatpreventtheseproteinsfromforming.125,theanimalshavenorecollectionofthethingsthattookplaceshortlyafterthedrugwastaken.Fromthisresearch,scientistsactuallyfoundawaytotargetlong-termmemoriesfor126.Yousee,everysingletimeyourememberamemory,yourbrainisonceagainfiringandrewiring.

Infact,eachtimeyoureflectonamemory,youarephysicallychangingthatmemoryinyourmind.Andeachtimethememoryischangedalittle,itreflectsyour127thoughts.Remembering,toagreatextent,isanactof128andimagination,whichmeansthatthemoreyoureflectonoldmemories,thelessaccuratetheywillbecome.Andscientistshaveactuallyquantifiedthischange.

After9/11,hundredsofpeoplewereaskedabouttheirmemoriesofthedreadfulday.Ayearlater,37%ofthedetailshadchanged.By2023,nearly50%ofthedetailshadchangedorgone129.Andbecausememoriesareformedandrebuilteverytime,ifyouadminister(服藥)theprotein-preventingdrugwhilerecallingamemory,thememorycanbe130removed.

Totestthis,scientiststooklabratsandplayedsoundforthem,shortlyfollowedbyanelectricshock.131doingthisformanytimes,theratsquicklylearnedthatiftheyheardthesound,ashockwassoontofollow.Therefore,theywouldstressupandfreezeeverytimetheyheardit.Monthslater,theseratswouldstill132thenoise.However,iftheyadministeredthedrugfirst,theratswouldlosethememoryofthesound,andsimplycontinueon.Theyhadlosttheirmemoryofthatspecificnoise.

Tobesurethatthedrugwasn’tjustcausinglarge-scalebraindamage,scientistsrepeatedtheseexperimentswithvarioustonesthistime.Bothsoundswouldwarnforashockand133theratswouldfearboth.Butiftheyadministeredthedrugandplayedonlyoneofthesounds,themicewouldonlyforgetthatonetone,whilestillremaining134oftheother.Overtimescientistshavediscoveredspecificdrugstotargetparticularproteinsacrossdifferentpartsofthebrain.

120．A．refreshB．forgetC．controlD．erase

121．A．rangeB．processC．ideaD．structure

122．A．incorrectB．evidentC．partialD．complex

123．A．eliminatingB．decreasingC．bringingD．building

124．A．inspiredB．stoppedC．identifiedD．perfected

125．A．BycontrastB．OnthecontraryC．AsaresultD．Forexample

126．A．evaluationB．estimationC．deletionD．production

127．A．terrifiedB．criticalC．currentD．former

128．A．repetitionB．creationC．functionD．reproduction

129．A．uncontrolledB．complicatedC．valuableD．missing

130．A．repeatedlyB．effectivelyC．hardlyD．consistently

131．A．BeforeB．UntilC．AfterD．While

132．A．turntoB．respondtoC．a(chǎn)dapttoD．returnto

133．A．surprisinglyB．especiallyC．eventuallyD．similarly

134．A．suspiciousB．carefulC．painfulD．fearful

Competitionisgoodforbusinesses.Intheworldofnavigation(導(dǎo)航)systems,however,competitionisalsoanecessity–itmaynotbewisetorelyonforeignsystemsforpositioningandtrackingservices.Now,135remarkableaccuracyandreliability,China’sBeiDousystemhasmadeitspresencefelt.

TheBeiDouprojectwassetupin1994.ThefirstBeiDousatellitewasnotlauncheduntil2000.Now,136,therearealreadymorethan20BeiDousatellitesinorbit(軌道).Theyforma137networkthatprovidespositioning,navigationandtimingservicesforChinaandseveralotherAsiancountries.

This“home-grown”systemisnow138amajorupgrade.Earlierthismonth,twoBeiDou-3satellites,thefirstofChina’smostpowerful139ofnavigationsatellites,werelaunchedintospace.Thelaunchmarksthebeginningoftheglobal140oftheBeiDounavigationsystem.Overthenextthreeyears,Chinaplanstosendup30moreBeiDou-3satellites;Theexpandednavigationsystemwill141createanetworkthatisabletosupportmilitaryandcivilianapplicationsaroundtheworld.

Scientistsinvolvedintheprojectsaidthenewsystemwouldgivecivilianusersanaccuracyof2.5meterstofivemeters,overtakingthatofthe142positioningtechnologies.BeiDou’schiefdesignersaidthenewsatelliteswouldbeableto143whichlaneacarisusingonamotorwayand144theswingofabuildinginhighwinds.Itwillalsobeabletoguidefiretruckstothenearestwaterhydrant(消防栓).TheChinesemilitary,meanwhile,willbeabletousecodedsignalsformillimeter(毫米)145.

Chinaisonlythethirdcountryintheworldtodevelopanavigationsystemonitsown,aftertheUnitedStates(GPS)andRussia(GLONASS).DevelopingBeiDouisanecessity.Thesystem146nationalsecuritybyendingarelianceonforeignsystems.Moreover,itenhancesChina’sinternationalreputationfortechnological147.

Formostofus,thebenefitsofthenewsatellitesystemwillbefeltinacoupleofyearswhenmorephonesare148withBeiDouchips(芯片).ManysmartphonestodaystilluseGPSandGLONASS.That’llsoonchangewiththedevelopmentofBeiDou.Oneproductmanager149mostsmartphonestobeabletoreceiveBeiDousignals.Hesays:“Inthreeyears’time,peoplemaystillsay‘I’musingGPS’,butinfact,theirphoneistuneintoBeiDou.”

135．A．dominatingB．boastingC．shiftingD．inputting

136．A．howeverB．a(chǎn)fterwardsC．moreoverD．therefore

137．A．continentalB．localC．domesticD．regional

138．A．enduringB．encounteringC．undergoingD．processing

139．A．generationB．informationC．examinationD．revolution

140．A．extensionB．expansionC．interactionD．invasion

141．A．objectivelyB．eventuallyC．sufficientlyD．essentially

142．A．existingB．progressingC．upcomingD．everlasting

143．A．exploreB．investigateC．spotD．remind

144．A．detectB．preventC．protectD．a(chǎn)djust

145．A．privacyB．a(chǎn)ccuracyC．fluencyD．currency

146．A．convincesB．insuresC．highlightsD．strengthens

147．A．innovationB．consumptionC．emissionD．exhibition

148．A．decoratedB．furnishedC．equippedD．connected

149．A．respectsB．instructsC．inspectsD．expects

Spaceexplorationhasalwaysbeentheprovinceof150:Thehumanimaginationreadilysoarswherehumaningenuity(創(chuàng)造力)strugglestofollow.AVoyagetotheMoon,oftencitedasthefirstsciencefictionstory,waswrittenbyCyranodeBergeracin1649.Cyranowasdeadandburiedforagoodthreecenturies151thefirstmannedrocketsstartedtofly.

In1961,whenPresidentKennedydeclaredthatAmericawouldsendamantothemoonbythedecade’send,thosewords,too,hada152quality.Theyresonated(共鳴)withoptimismand153inmuchthesamewayasthemostfamous154speechofall,deliveredbyMartinLutherKingJr.twoyearslater.Bytheendofthedecade,bothvisionshadyieldedconcreteresultsand155Americansociety.156,inmanywaysthetwodreamsendedup157