接入网分层模型中接入承载处理功能层、电路层和通道层构成了传送层。

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Icertainlydidn’tintendto_____yourplans.

A、upset
B、shake
C、shave
D、drag

Passage4

Questions16to20arebasedonthefollowingpassage:

Thenewglobalsatellitecommunicationssystemswillofferthreekindsservice,whichmayoverlapinmanydifferentkindsofreceivers.

VOICE.SatellitetelephoneswillbeabletomakecallsfromanywhereontheEarthtoanywhereelse.Thatcouldmakethemespeciallyusefultoremote,thirdworldvillages(someofwhichalreadyusestationarysatellitetelephones),explorersanddisaster-reliefteams.Today’smobiletelephonesdependonearth-boundtransmitters,wheretechnicalstandardsvaryfromcountrytocountry.Sobusinesstravelerscannotusetheirmobilephonesoninternationaltrips.Satellitetelephoneswouldmakethatpossible.

MESSAGING.Satellitemassagershavethesameglobalcoverageassatellitetelephones,butcarrytextalone,whichcouldbeusefulforthosewithlaptopcomputers.Equippedwithasmallscreenliketoday’spapers,satellitemassagerswillalsoreceiveshortmessages.

TRACKING.Voiceandmessagingsystemswillalsotelltheiruserswheretheyaretowithinafewhundredmeters.Combinedwiththemessagingservice,thelocationservicecouldhelprescueteamstofindstrandedadventurers,thepolicetofindstolencars,exporterstofollowtheprogressofcargoes,andhaulagecompaniestocheckthatdriversarenotdetouringthepub.America’smilitaryGlobalPositioningSystem(GPS)satellitewillprovidebetterpositioninginformationtoanyonewhohasareceiverfortheirsignals,butGPSdoesnotcarrymessages,sosuchareceivercannotbeusedonitsownfortrackingorrescue.Bythemid-1990s,GPSreceiverswillbeabletotellpeoplewheretheyaretowithin70metersanywhereintheworld,andtowithinameterorsoinareaswheretheserviceissupplementedbyground-basedtransmitter.

16.Globalsatellitecommunicationssystemswillbeusefulto.

A.laptopcomputerusers

B.remotevillages

C.disaster-reliefteams

D.allabove

17.Satellitetelephonewillmake.

A.businesstravelersusemobilephonesoninternationaltrips

B.possiblecallsfromanywhereonearthtoanywhereelse

C.explorershappy

D.allabove

18.Whichofthefollowingistrue?

A.ThepositioningprecisionofthevoicesystemisbetterthanthatofGPS.

B.ThepositioningprecisionofGPSisBetterthanthatofthevoicesystem.

C.ThepositioningprecisionofthemessagingsystemisbetterthanofGPS.

D.Thepositioningprecisionofvoicesystemisbetterthanthatofthemessagingsystem.

19.Whatcanwesayaboutthenewglobalsatellitecommunicationssystems?

A.Theyarewidelyused.

B.Theyareveryhelpful.

C.Theyarecostly.

D.BothAandB.

20.Whichofthefollowingmaybethebesttitleforthepassage?

A.GlobalSatelliteCommunications

B.NewVoiceandMessagingSystem

C.NewGenerationSatellite

D.AlwaysinTouch

Thevisitorsplannedto________________(花最少的时间游览公园以外的地方).

Withoutregularsuppliesofsomehormonesourcapacitytobehavewouldbeseriouslyimpaired;withoutotherswewouldsoondie.Tinyamountsofsomehormonescanmodifymoodsandactions,ourinclinationtoeatordrink,ouraggressivenessorsubmissiveness,andourreproductiveandparentalbehavior.Andhormonesdomorethaninfluenceadultbehavior;earlyinlifetheyhelptodeterminethedevelopmentofbodilyformandmayevendetermineanindividual’sbehavioralcapacities.Laterinlifethechangingoutputsofsomeendocrineglandsandthebody’schangingsensitivitytosomehormonesareessentialaspectsofthephenomenaofaging.

Communicationwithinthebodyandtheconsequentintegrationofbehaviorwereconsideredtheexclusiveprovinceofthenervoussystemuptothebeginningofthepresentcentury.TheemergenceofendocrinologyasaseparatedisciplinecanprobablybetracedtotheexperimentsofBaylissandStarlingonthehormonesecretion.Thissubstanceissecretedfromcellsintheintestinalwallswhenfoodentersthestomach;ittravelsthroughthebloodstreamandstimulatesthepancreastoliberatepancreaticjuice,whichaidsindigestion.Byshowingthatspecialcellssecretchemicalagentsthatareconveyedbythebloodstreamandregulatedistanttargetorgansortissues.Baylissandstarlingdemonstratedthatchemicalintegrationcouldoccurwithoutparticipationofthenervoussystem.

Theterm“hormone”wasfirstusedwithreferencetosecretion.StarlingderivedthetermfromtheGreekhormone,meaning“toexciteorsetinmotion.Theterm“endocrine”wasintroducedshortlythereafter“Endocrine”isusedtorefertoglandsthatsecretproductsintothebloodstream.Theterm“endocrine”contrastswith“exocrine”,whichisappliedtoglandsthatsecrettheirproductsthoughductstothesiteofaction.Examplesofexocrineglandsarethetearglands,thesweatglands,andthepancreas,whichsecretspancreaticjuicethroughaductintotheintestine.Exocrineglandsarealsocalledductglands,whileendocrineglandsarecalledductless.

1.Whatistheauthor’smainpurposeinthepassage?

A.Toexplainthespecificfunctionsofvarioushormones.

B.Toprovidegeneralinformationabouthormones.

C.Toexplainhowtheterm“hormone”evolved.

D.Toreportonexperimentsinendocrinology.

2.Thepassagesupportswhichofthefollowingconclusions?

A.Thehumanbodyrequireslargeamountsofmosthormones.

B.Synthetichormonescanreplaceaperson’snaturalsupplyofhormonesifnecessary.

C.Thequantityofhormonesproducedandtheireffectsonthebodyarerelatedtoaperson’sage.

D.Theshortchildoftallparentsverylikelyhadahormonedeficiencyearlyinlife.

3.ItcanbeinferredfromthepassagethatbeforetheBaylissandStarlingexperiments,mostpeoplebelievedthatchemicalintegrationoccurredonly___.

A.duringsleep.

B.intheendocrineglands.

C.undercontrolofthenervoussystem.

D.duringstrenuousexercise.

4.Theword“liberate”couldbestbereplacedbywhichofthefollowing?

A.EmancipateB.DischargeC.SurrenderD.Save

5.Accordingtothepassageanothertermforexocrineglandsis___.

A.ductglands

B.endocrineglands

C.ductlessglands

D.intestinalglands.

Passage3

Questions11to15arebasedonthefollowingpassage:

UnliketheirAmericanorEuropeancounterparts,carsalesmeninJapanworkhardtogetabuyer.Insteadoflyinglazilyaroundshowroomswaitingforcustomerstodropby,manyJapanesecarsalesmenstillgoouttogetthem.Theywalkwearilyalongthestreetscarsdoor-to-door.Newcustomersarehuntedwithfruitandcakesontheirbirthdays.Butlifeisgettingtough,andnotjustbecausenew-carsalesarefalling.

WithmoreJapanesewomen(whooftencontrolthehouseholdbudget)goingouttowork,thesalesmenincreasinglyfindnobodyathomewhentheycall.Thatmeansanothervisitintheeveningortheweekend.Thentheyfaceanextraproblem:morepeople,especiallytheyoung,prefertochooseanewcarfromashowroomwheretheycancomparedifferentmodels.

Evenaslateasthemid-1980ssome90%ofnewcarsweresolddoor-to-door.Insomeruralareasmostnewcarsarestillsoldthisway.Butinthebigcitiesmorethanhalfthenewcarsarenowsoldfromshowrooms.

AlthoughinvestinginshowroomsisexpensivebecauseofthehighcostofJapaneseland,dealershavelittlechoice.AlaborshortageandhigheramongJapan’sworkforcearemakingitdifficulttohiredoor-to-doorsalesmen.MostofaJapanesecarsalesman’sworkingdayisspentdoingfavorsforcustomers,likearranginginsuranceorpickingupvehiclesforservicing,ratherthanactuallyselling.

Japan’sdoorstepcarsalesmenarenotabouttovanish.Thepersonalservicetheyprovideissodeep-rootedinJapanthattheyarelikelytooperatealongsidetheglitteringnewshowrooms.Thetwosystemsevencomplementeachother.Whatincreasinglyhappensisthattheshowroomattractstheinterestofapotentialbuyer,givingthefootsoresalesmenafirmleadtofollowupwithahomevisit.

11.Japanesecarsalesusuallydonotwaitatshowroomsforcustomerstodropby;instead,.

A.theysellcarsdoor-to-door

B.theybuypresentsfortheircustomers

C.theyenjoythemselvesinrecreationcenters

D.theygoouttodomarketresearches

12.Impliedbutstated:thecompetitionincarmarketis.

A.lightB.moderateC.fierceD.unfair

13.Youngpeopleliketobuyanewcar.

A.athomeB.fromashowroom

C.madeintheU.S.A.D.madeinJapan

14.ThesquadronofJapanesecarsalesmenisreducingbecauseof.

A.alaborshortage

B.higherexpectationsamongJapan’sworkforce

C.highcostland

D.bothAandB

15.Japanesecarsalesmentotheircustomersmanyfavorssuchas.

A.showingthemaroundinanexhibition

B.arranginginsurance

C.payingthemavisitonweekends

D.sellingolecarsforthem

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