专题限时训练(三十三)[史地自然型阅读理解(一)](限时：25分钟)(一)InAmerica,VirginiaBeachhasalltheelementsofaclassicseasideresort:brilliantbeaches,alivelyboardwalk,plentyofrestaurantsandnightspots,andamusementridessuretoappealtokids.ManybelieveVirginiaBeachisatitsbestintheoffseason,whenthetownislesscrowdedbuttheweatherisstillmild.Meanwhile,somesafetytipsshouldbefollowed,enjoyingthehappinessandexcitementthebeachoffers.Thenumber1safetytipconcernsoceansafety:payattentiontoflagconditionspostedonthelifeguardstands.Lifeguardspostaredflagtowarnwhentheoceanwaterisdangerous.Takethemseriously!Touristsfromlandlockedregionsareparticularlyeasilyattractedbythemagicofthewaves.However,acalmoceancanbecomeriskywithoutwarning.Makesureyouswimnearalifeguard.Swimmingwithoutlifeguardprotectionisalmostfivetimesasgreatasdrowningatabeachwithlifeguards.Neverswimalone.Manydrowningsinvolvesingleswimmers.Whenyouswimwithsomeoneelse,ifoneofyouhasaproblem,theothermaybeabletogethelp,includingsignalingforassistancefromothers.Don'tfightthecurrent.Thefactsshowthatsome80%ofrescuesbylifeguardsatoceanbeachesarecausedbycurrents.Thesecurrentsareformedbysurfandgravity,becauseoncesurfpusheswateruptheslopeofabeach,gravitypullsitback.Thiscancreateconcentratedriversofwatermovingoffshore.Ifyouarecaughtinaripcurrent,don'tfightitbytryingtoswimdirectlytoshore.Instead,swimparalleltoshoreuntilyoufeelthecurrentrelax,thenswimtoshore.Mostripcurrentsarenarrowandashortswimparalleltoshorewillhelpbringyoutosafety.1.WhencomingtoVirginiaBeach,childrencannotenjoythehappinessof________.A.walkingontheroadmadeofwoodB．joiningthenightspotsC．ridingahorseorapumpercarD．skiinginthesea2.ManypeoplebelievethebesttimetovisitVirginiaBeachmaybe________.A.afterautumnschooltermbeginningB．inthesummervacationC．duringtheChristmasholidayD．inthecoldwinter3.Swimmingintheseayou'dbetternotswim________.A.withafriendB．withinthesightofthelifeguardC．withthecurrentD．asfarasyoulike4.Fromthepassage,wecanknow________.A.oneinfivepersonsswimmingintheseaisdrownedB．ifonewithalifeguardweredrowning,fivepersonswithoutlifeguardswouldbeC．some80%peopledrowningbythecurrentsarerescuedbylifeguardsD．some20%drowningbythecurrentsarerescuedbylifeguards5.Thepassagemainlytellsus________.A.VirginiaBeachhasalltheelementsofaclassicseasideresortB．thehappinessandexcitementthebeachoffersC．somesafetytipswhenswimmingintheseaD．thedangersfortouristsfromlandlockedregionstoswiminthesea(二)Wind，water，fireandice—thesepowerfulnaturalforceshaveshapedthelandofAmericainthepast.Theyarestillchangingittoday.TheColoradoRiverslowlycutdownthroughstonetomaketheGrandCanyon(大峡谷)．Longago，icesheetscutYosemiteValleyandtheGreatLakes，andglaciers(冰川)arestillonthemoveinAlaska.Windandrainstormhitthelandfromtimetotime.Firessometimesburndownforestsanddestroythehomesofwildanimals:ThishappenedinYellowstoneParkin1988.Deadvolcanic(火山的)mountainssuchasHaleakalaonMauiandCarterLakeinOregonarebeautifultolookat.ButthereareseveralactivevolcanoesintheUS，especiallyalongthePacificCoast.Therearealsomanyearthquakesinthisarea.Scientistscandonothingtocontrolearthquakesorvolcanoes.ThiswasshownclearlyonMay18,1980.At8:32thatmorning，MountStHelensinWashingtonstatebrokeout.Thetopofthemountainwasblownoff.Over60people—campers，scientists，journalists，forestworkers—werekilled.Hundredsofsquaremilesofforestswereknocke...
