若干个对称振子组阵,就能够控制辐射,产生“扁平的面包圈”,把信号进一步集中到在水平面方向上,从而获得增益和更好的方向性。

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Iftheoldmaximthatthecustomerisalwaysrightstillhasmeaning,thentheairlinesthatplytheworld’sbusiestairroutebetweenLondonandParishaveaflightontheirhands.

TheEurostartrainservicelinkingtheUKandFrenchcapitalsviatheChannelTunneliswinningcustomersinincreasingnumbers.InlateMay,itcarrieditsonemillionthpassenger,havingrunonlyalimitedservicebetweenLondon,ParisandBrusselssinceNovember1994,startingwithtwotrainsadayineachdirectiontoParisandBrussels.By1997,thecompanybelievesthatitwillbecarryingtenmillionpassengersayear,andcontinuetogrowfromthere.

FromJuly,EurostarstepsitsservicetoninetrainseachwaybetweenLondonandParis,andfivebetweenLondonandBrussels.Eachtraincarriesalmost800passengers,210oftheminfirstclass.

Theairlinesestimatethattheywillinitiallylosearound15%-20%oftheirLondon-ParistraffictotherailwaysonceEurostarstartsafullservicelaterthisyear(1995),with15trainsadayeachway.AsimilarservicewillstarttoBrussels.Thedamagewillbelimited,however,theairlinesbelieve,withpassengernumbersreturningtopreviouslevelswithintwotothreeyears.

Intheshortterm,thedamagecausedbythe1millionpeople-levelstravelingbetweenLondonandParisandBrusselsonEurostartrainsmeansthatsomeairservicesarealreadysuffering.Someofthemajorcarrierssaythattheirpassengernumbersaredownbylessthan5%andpointtotheirrivals-ParticularlyAirFrance-ashavingsufferedtheproblems.OntheBrusselsroute,therailwaycompanyhadlesssuccess,andtheairlinesreportanythingfromarounda5%droptonovisibledeclineintraffic.

Theairlines’optimismonreturningtrafficlevelsisbasedonhistoricalprecedent.BritishMidland,forexample,pointstoitsexperienceonHeathrowLeedsBradfordservicewhichsawpassengernumbersfoldby15%whenBritishRailelectrifiedandmodernizedtherailwaylinebetweenLondonandYorkshire.Twoyearslater,travelhadrisenbetweenthetwodestinationstothepointwheretheairlinewascarryingrecordnumbersofpassengers.

1.Britishairlinesconfideinthefactthat__.

A.theyaremorepowerfulthanotherEuropeanairlines.

B.theirtotallosswon’tgobeyondadropof5%passengers.

C.theirtrafficlevelswillreturnin2-3years.

D.travelingbyrailcannevercatchupwithtravelingbyair.

2.Theauthor’sattitudetowardsthedropofpassengersmaybedescribedas__.

A.worried.B.delightedC.puzzled.D.unrivaled.

3.Inthepassage,BritishRail(Para6)ismentionedto__.

A.provideacomparisonwithEurostar.

B.supporttheairlines’optimism.

C.provetheinevitabledropofairpassengers.

D.callforelectrificationandmodernizationoftherailway.

4.Therailway’sBrusselsrouteisbroughtforthtoshowthat__.

A.theEurostartrainserviceisnotdoinggoodbusiness.

B.theairlinescanwellcompetewiththerailway.

C.theEurostartrainserviceonlycausedlittledamage.

D.onlysomeairlines,suchasAirFrance,aresuffering.

5.Thepassageistakenfromthefirstofanessay,fromwhichwemaywellpredictthatinthefollowingparttheauthorisgoingto__.

A.praisetheairlines’clear-mindedness.

B.warntheairlinesofhigh-speedrailservices.

C.proposeareductionofLondon/Parisflights.

D.advisetheairlinestofollowBritishMidlandastheirmodel.

PartIReadingComprehension

Directions:Inthisparttherearefourpassages.Eachpassageisfollowedbyfourcomprehensionquestions.Readthepassageandanswerthequestions.ThenmarkyouranswerontheAnswerSheet.

Passage1

Questions1to5arebasedonthefollowingpassage:

Askthreepeopletolookthesamewindowatabusystreetcornerandtellyouwhattheysee.Chancesareyouwillreceivethreedifferentanswers.Eachpersonseesthesamescene,buteachperceivessomethingdifferentaboutit.

Perceivinggoesoninourminds.Ofthethreepeoplewholookoutthewindow,onemaysaythatheseesapolicemangivingamotoristaticket.Anothermaysaythatheseesarush-hourtrafficjamattheintersection.Thethirdmaytellyouthatheseesawomantryingtocrossthestreetwithfourchildrenintow.Forperceptionisthemind’sinterpretationofwhatthesenses—inthiscaseoureyes—tellus.

Manypsychologiststodayareworkingtotrytodeterminejusthowapersonexperiencesorperceivestheworldaroundhim.Usingascientificapproach,thesepsychologistssetupexperimentsinwhichtheycancontrolallofthefactors.Bymeasuringandchartingtheresultsofmanyexperiments,theyaretryingtofindoutwhatmakesdifferentpeopleperceivetotallydifferentthingsaboutthesamescene.

1.Seeingandperceivingare.

A.thesameaction

B.twoseparateactions

C.twoactionscarriedonentirelybyeyes

D.severalactionsthattakeplaceatdifferenttimes

2.Perceivingisanactionthattakesplace.

A.inoureyes

B.onlywhenwethinkveryhardaboutsomething

C.onlyunderthedirectionofapsychologist

D.ineveryperson’smind

3.Peopleperceivedifferentthingsaboutthesamescenebecause.

A.theyseedifferentthingsB.somehavebettereyesight

C.theycannotagreeaboutthingsD.noneofthese

4.Whichofthefollowingisimpliedbutnotstatedinthepassage?

A.Psychologistsdonotyetknowpeoplesee.

B.Theexperimentsinwhichallfactorsarecontrolledarebetter.

C.Thestudyofperceptionisgoingonnow.

D.Perceptiondoesnotinvolvepsychologicalfactors.

5.Thebesttitleforthisselectionis.

A.HowWeSee

B.LearningaboutOurMindsthroughScience

C.WhatPsychologistsPerceive

D.HowtoBecauseanExperimentalPsychologist

.IfyouhavereallybeenstudyingEnglishforsolong,it’sabouttimeyou_____abletowritelettersinEnglish.

A、shouldbe
B、were
C、mustbe
D、are

AccordingtoStevenYoung,ifscientistsgetthedatathat________,theywouldpetitionforfasttrackstatus.

Scatteredthroughtheseasoftheworldarebillionsoftonsofsmallplantsandanimalscalledplankton.Mostoftheseplantsandanimalsaretoosmallforthehumaneyetosee.Theydriftaboutlazilywiththecurrents,providingabasicfoodformanylargeranimals.Planktonhasbeendescribedastheequivalentofthegrassesthatgrowonthedrylandcontinents,andthecomparisonisanappropriateone.Inpotentialfoodvaluehowever,planktonfaroutweighsthatofthelandgrasses.Onescientisthasestimatedthatwhilegrassesoftheworldproduceabout49billiontonsofvaluablecarbohydrateseachyear.Thesea’splanktongeneratesmorethantwiceasmuch.

Despiteitsenormousfoodpotential,littleeffortwasmadeuntilrecentlytofarmplanktonaswefarmgrassesonland.Nowmarinescientistshaveatlastbeguntostudythispossibility,especiallyasthesea’sresourcesloomevenmoreimportantasameansoffeedinganexpandingworldpopulation.

Nooneyethasseriouslysuggestedthat“planktonburgers”maysoonbecomepopulararoundtheworld.Asapossiblefarmedsupplementaryfoodsource,however,planktonisgainingconsiderableinterestamongmarinescientists.

Onetypeofplanktonthatseemstohavegreatharvestpossibilitiesisatinyshrimplikecreaturecalledkrill.Growingtotwoorthreeincheslong,krillprovidethemajorfoodforthegiantbluewhale,thelargestanimalevertoinhabittheEarth.Realizingthatthiswhalemaygrow100feetandweigh150tonsatmaturity,itisnotsurprisingthateachonedevoursmorethanonetonofkrilldaily.

Krillswimaboutjustbelowthesurfaceinhugeschoolssometimesmileswide,mainlyinthecoldAntarctic.Becauseoftheirpinkcolor,theyoftenappearasasolidreddishmasswhenviewedfromashiporfromtheair.Krillareveryhighinfoodvalue.Apoundofthesecrustaceanscontainsabout460calories—aboutthesameasshrimporlobster,towhichtheyarerelated.

Ifthekrillcanfeedsuchhugecreaturesaswhales,manyscientistsreason,theymustcertainlybecontendersasnewfoodsourceforhumans.

1.Whichofthefollowingbestportraystheorganizationofthepassage?

A.Theauthorpresentstheadvantagesanddisadvantagesofplanktonasafoodsource.

B.Theauthorquotespublicopiniontosupporttheargumentforfarmingplankton.

C.Theauthorclassifiesthedifferentfoodsourcesaccordingtoamountofcarbohydrate.

D.Theauthormakesageneralstatementaboutplanktonasafoodsourceandthenmovestoaspecificexample.

2.Accordingtothepassage,whyisplanktonregardedtobemorevaluablethanlandgrasses?

A.Itiseasiertocultivate.

B.Itproducesmorecarbohydrates.

C.Itdoesnotrequiresoil.

D.Itismorepalatable.

3.Whydoestheauthormention“planktonburgers”?

A.Todescribetheappearanceofonetypeofplankton.

B.Toillustratehowmuchplanktonawhaleconsumes.

C.Tosuggestplanktonasapossiblefoodsources.

D.Tocomparethefoodvaluesofbeefandplankton.

4.Whatismentionedasoneconspicuousfeatureofkrill?

A.Theyarethesmallestmarineanimals.

B.Theyarepinkincolor.

C.Theyaresimilarinsizetolobsters.

D.Theyhavegrasslikebodies.

5.Theauthormentionsallofthefollowingasreasonswhyplanktoncouldbeconsideredahumanfoodsourceexceptthatitis___.

A.highinfoodvalue.

B.inabundantsupplyintheoceans.

C.anappropriatefoodforotheranimals.

D.freeofchemicalsandpollutants.

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