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卫星通信是利用人造地球卫星作为()来转发无线电波而进行的两个或多个地球站之间的通信。

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Whatdoesthefutureholdfortheproblemofhousing?Agooddealdepends,ofcourse,onthemeaningof“future”.Ifoneisthinkingintermsofsciencefictionandthespaceage,itisatleastpossibletoassumethatmanwillhavesolvedsuchtrivialandearthlyproblemsashousing.Writersofsciencefiction,fromH.G.Wellsonwards,havehadlittletosayonthesubject.Theyhaveconveyedthesuggestionthatmenwillliveingreatcomfort,witheveryconceivableapparatustomakelifesmooth,healthyandeasy,ifnothappy.Buttheyhavenotsaidwhathishousewillbemadeof.Perhapssomenewbuildingmaterial,asyetunimagined,willhavebeendiscoveredorinventedatleast.Onemaybecertainthatbricksandmortar(泥灰,灰浆)willlonghavegoneoutoffashion.

Buttheproblemsofthenextgenerationortwocanmorereadilybeimagined.Scientistshavealreadypointedoutthatunlesssomethingisdoneeithertorestricttheworld’srapidgrowthinpopulationortodiscoveranddevelopnewsourcesoffood(orboth),millionsofpeoplewillbedyingofstarvationoratthebestsufferingfromunderfeedingbeforethiscenturyisout.Butnobodyhasyetworkedoutanyplanforhousingthesegrowingpopulations.Admittedlytheworstsituationswilloccurinthehottestpartsoftheworld,wherehousingcanbelightstructureorinbackwardareaswherestandardsaretraditionallylow.Buteventheminimumshelterrequiresmaterialsofsomekindandintheteeming,bulgingtownsthelow-standard“housing”offlattenedpetrolcansanddirtycanvasisfarmorewastefulofgroundspacethancanbetolerated.

Sincethewar,HongKonghassufferedthekindofcrisiswhichislikelytoariseinmanyotherplacesduringthenextgeneration.Literallymillionsofrefugeesarrivedtoswellthealreadygrowingpopulationandemergencystepshadtobetakenrapidlytopreventsqualor(肮脏)anddiseaseandthespreadcrime.Thecityistacklingthesituationenergeticallyandenormousblocksoftenements(贫民住宅)arerisingatanastonishingaped.ButHongKongisonlyonesmallpartofwhatwillcertainlybecomeavastproblemandnotmerelyahousingproblem,becausewhenpopulationgrowsatthisratethereareaccompanyingproblemsofeducation,transport,hospitalservices,drainage,watersupplyandsoon.NoteveryareamaygivethesameresourcesasHongKongtodrawuponandthesearchforquickerandcheapermethodsofconstructionmustnevercease.

1.Whatistheauthor’sopinionofhousingproblemsinthefirstparagraph?

A.Theymaybecompletelysolvedatsometimeinthefuture.

B.Theyareunimportantandeasilydealtwith.

C.Theywillnotbesolveduntilanewbuildingmaterialhasbeendiscovered.

D.Theyhavebeendealtwithinspecificdetailinbooksdescribingthefuture.

2.Thewriterissurethatinthedistantfuture___.

A.bricksandmortarwillbereplacedbysomeotherbuildingmaterial.

B.anewbuildingmaterialwillhavebeeninvented.

C.bricksandmortarwillnotbeusedbypeoplewhowanttheirhousetobefashionable.

D.anewwayofusingbricksandmortarwillhavebeendiscovered.

3.Thewriterbelievesthatthebiggestproblemlikelytoconfronttheworldbeforetheendofthecentury___.

A.isdifficulttoforesee.

B.willbehowtofeedtheevergrowingpopulation.

C.willbehowtoprovideenoughhousesinthehottestpartsoftheworld.

D.isthequestionoffindingenoughgroundspace.

4.Whenthewritersaysthattheworstsituationswilloccurinthehottestpartsoftheworldorinbackwardareas,heisreferringtothefactthatintheseparts___.

A.standardsofbuildingarelow.

B.onlyminimumshelterwillbepossible.

C.thereisnotenoughgroundspace.

D.thepopulationgrowthwillbethegreatest.

5.WhichofthefollowingsentencesbestsummarizesParagraph3?

A.HongKonghasfacedaseriouscrisiscausedbymillionsofrefugees.

B.HongKonghassuccessfullydealtwiththeemergencycausedbymillionsofrefugees.

C.HongKong’scrisiswasnotonlyamatterofhousingbutincludedanumberofotherproblemsofpopulationgrowth.

D.ManypartsoftheworldmayhavetofacethekindofproblemsencounteredbyHongKongandmayfinditmuchhardertodealwiththem.

The____ofAIDShasledtoanexpansioninresearchseekingacure.

Recentresearchhasclaimedthatanexcessofpositiveionsintheaircanhaveanilleffectonpeople’sphysicalorpsychologicalhealth.Whatarepositiveions?Well,theairisfullofions,electricallychargedparticles,andgenerallythereisaroughbalancebetweenthepositiveandthenegativecharged.Butsometimesthisbalancebecomesdisturbedandalargerproportionofpositiveionsarefound.Thishappensnaturallybeforethunderstorm,earthquakeswhenwindssuchastheMistral,HamsinorSharavareblowingincertaincountries.Oritcanbecausedbyabuild-upofstaticelectricityindoorsfromcarpetsorclothingmadeofman-madefibres,orfromTVsets,duplicatorsorcomputerdisplayscreens.

Whenalargenumberofpositiveionsarepresentintheairmanypeopleexperienceunpleasanteffectssuchasheadaches,fatigue,irritability,andsomesensitivepeoplesuffernauseaorevenmentaldisturbance.Animalsarealsoaffected,particularlybeforeearthquakes,snakeshavebeenobservedtocomeoutofhibernation,ratstofleefromtheirburrows,dogshowlandcatsjumpaboutunaccountably.ThishasledtheUSGeographicalSurveytofundanetworkofvolunteerstowatchanimalsinanefforttoforeseesuchdisastersbeforetheyhitvulnerableareassuchasCalifornia.

Conversely,whenlargenumbersofnegativeionsarepresent,thenpeoplehaveafeelingofwell-being.Naturalconditionsthatproducetheselargeamountsarenearthesea,closetowaterfallsorfountains,orinanyplacewherewaterissprayed,orformsaspray.Thisprobablyaccountsforthebeneficialeffectofaholidaybythesea,orinthemountainswithtumblingstreamsorwaterfalls.

Toincreasethesupplyofnegativeionsindoors,somescientistsrecommendtheuseofionisers:smallportablemachines,whichgeneratenegativeions.Theyclaimthationisersnotonlycleanandrefreshtheairbutalsoimprovethehealthofpeoplesensitivetoexcesspositiveions.Ofcourse,therearethedetractors,otherscientists,whodismisssuchclaimsandareskepticalaboutnegative/positiveionresearch.Thereforepeoplecanonlymakeuptheirownmindsbyobservingtheeffectsonthemselves,oronothers,ofanegativerichorpoorenvironment.Afterallitisdebatablewhetherdependingonseismicreadingstoanticipateearthquakesismoreeffectivethanwatchingthecat.

1.Whateffectdoesexceedingpositiveionizationhaveonsomepeople?

A.Theythinktheyareinsane.

B.Theyfeelratherbad-temperedandshort-fussed.

C.Theybecomeviolentlysick.

D.Theyaretootiredtodoanything.

2.Inaccordancewiththepassage,staticelectricitycanbecausedby___.

A.usinghome-madeelectricalgoods.

B.wearingclothesmadeofnaturalmaterials.

C.walkingonartificialfloorcoverings.

D.copyingTVprogramsonacomputer.

3.Ahighnegativeioncountislikelytobefound___.

A.nearapoundwithawaterpump.

B.closetoaslow-flowingriver.

C.highinsomebarrenmountains.

D.byarotatingwatersprinkler.

4.Whatkindofmachinecangeneratenegativeionsindoors?

A.Ionisers.

B.Air-conditioners.

C.Exhaust-fans

D.Vacuumpumps.

5.Somescientistsbelievethat___.

A.watchinganimalstoanticipateearthquakesismoreeffectivethandependingonseismography.

B.theunusualbehaviorofanimalscannotbetrusted.

C.neitherwatchingnorusingseismographsisreliable.

D.earthquake

翻译:

中国位于亚洲东部,是世界上人口最多的国家。中国是世界四大文明古国之一,拥有大量的中华文化光辉的古迹,此外,中国地大物博,拥有茂密的森林、雄伟壮丽的瀑布、秀丽的湖泊以及如利剑直插云霄的山峰,所有这些都令世界各国人民神往。但是,更重要的是,中国以拥有五千多年的历史而自豪,遗留下无数的历史文物,其中包括珍贵珠宝、古迹名胜、宫殿及数不尽的雄伟建筑,令人惊叹不已。这种种原因都促使中国成为许多人梦寐以求的旅游胜地。

Inthelast12yearstotalemploymentintheUnitedStatesgrewfasterthanatanytimeinthepeacetimehistoryofanycountry–from82to110millionbetween1973and1985–thatis,byafullonethird.Theentiregrowth,however,wasinmanufacturing,andespeciallyinno–blue-collarjobs…

Thistrendisthesameinalldevelopedcountries,andis,indeed,evenmorepronouncedinJapan.Itisthereforehighlyprobablethatin25yearsdevelopedcountriessuchastheUnitedStatesandJapanwillemploynolargeraproportionofthelaborforceInmanufacturingthandevelopedcountriesnowemployinfarming–atmost,10percent.TodaytheUnitedStatesemploysaround18millionpeopleinblue-collarjobsinmanufacturingindustries.By2010,thenumberislikelytobenomorethan12million.Insomemajorindustriesthedropwillbeevensharper.Itisquiteunrealistic,forinstance,toexpectthattheAmericanautomobileindustrywillemploymorethanone–thirdofitspresentblue-collarforce25yearshence,eventhoughproductionmightbe50percenthigher.

Ifacompany,anindustryoracountrydoesnotinthenextquartercenturysharplyincreasemanufacturingproductionandatthesametimesharplyreducetheblue-collarworkforce,itcannothopetoremaincompetitive–oreventoremain“developed.”Theattempttopreservesuchblue–collarjobsisactuallyaprescriptionforunemployment…

ThisisnotaconclusionthatAmericanpoliticians,laborleadersorindeedthegeneralpubliccaneasilyunderstandoraccept.WhatconfusestheissueevenmoreitthattheUnitedStatesisexperiencingseveralseparateanddifferentshiftsinthemanufacturingeconomy.Oneistheaccelerationofthesubstitutionofknowledgeandcapitalformanuallabor.Wherewespokeofmechanizationafewdecadesago,wenowspeakof“robotization“or“automation.”Thisisactuallymoreachangeinterminologythanachangeinreality.WhenHenryFordintroducedtheassemblylinein1909,hecutthenumberofman–hoursrequiredtoproduceamotorcarbysome80percentintwoorthreeyears–farmorethananyoneexpectstoresultfromeventhemostcompleterobotization.Butthereisnodoubtthatwearefacinganew,sharpaccelerationinthereplacementofmanualworkersbymachines–thatis,bytheproductsofknowledge.

1.Accordingtotheauthor,theshrinkageinthemanufacturinglaborforcedemonstrates______.

A.thedegreetowhichacountry’sproductionisrobotized

B.areductioninacountry’smanufacturingindustries

C.aworseningrelationshipbetweenlaborandmanagement

D.thedifferencebetweenadevelopedcountryandadevelopingcountry

2.Accordingtotheauthor,incoming25years,adevelopedcountryorindustry,inordertremaincompetitive,oughtto______.

A.reducethepercentageoftheblue-collarworkforce

B.preserveblue–collarjobsforinternationalcompetition

C.acceleratemotor–canmanufacturinginHenryFord’sstyle

D.solvetheproblemofunemployment

3.Americanpoliticiansandlaborleaderstendtodislike_____.

A.confusioninmanufacturingeconomy

B.anincreaseinblue–collarworkforce

C.internalcompetitioninmanufacturingproduction

D.adropintheblue–collarjobopportunities

4.Theword“prescription”in“aprescriptionforunemployment”maybetheequivalentto______

A.somethingrecommendedasmedicaltreatment

B.awaysuggestedtoovercomesomedifficulty

C.somemeasurestakeninadvance

D.adevicetodire

5.Thispassagemayhavebeenexceptedfrom________

A.amagazineaboutcapitalinvestment

B.anarticleonautomation

C.amotor-carmagazine

D.anarticleonglobaleconomy

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