题目内容：
SectionA Directions：Thereare4passagesinthispart．Eachpassageisfollowedbysomequestionsorunfinishedstatements．ForeachthemofthemareforchoicesmarkedA,B,candD.YoushoulddecideonthebestchoiceandblackenthecorrespondingletterontheAnswerSheetwithapencil.
Questions21to24arebasedonthefollowingpassage： Americansliketodobusinesswithoutleavingtheircars.You'llseedrive-inbanks，drive-inrestaurants，drive-inchurchesanddrive-inmovies. WhendrivingintheU.S.,it'sagoodideatohaveaninternationalriver'slicenseifyoudon'thaveastatelicense.Eachofthefiftystateshasitsowntrafficlaws。Getinformationwhenyoucrosstheborderintoastateatatouristinformationcenter． Thereisanationalspeedlimitof55milesperhour.Americansaregenerallypoliteaboutlettingcarsenterbusystreets.Theyusuallystopforpeoplewhoarewalkingtoletthemcrossthestreet.Inmanystatesyoumayturnrightafterstoppingatacorner,evenifthereisaredlight.Onsomeroadstheremaybeaminimumspeed. Ifyourentacar,askthecompanywhattodoincaseyourcarbreaksdown.Somecompanieswillaskyoutocallaspecialnumber.Otherswillwantyoutohavethe'carrepaired.Theywillpartlydeductthecostoftherepairfromyourbill. Mileage''canmeantwothings.Itmaymeanthetotalnumberofmilesacarhasbeendriven.Wesay“Thiscaronlyhas10,000milesonit;ithaslowmileage.”Ontheotherhand,“gasmileage”isthenumberofmilesacarcantravelononeU.S.gallonofgas.Forexample,abigcar hatgets25milestothegallongetsverygoodmileage.Asmalleconomycarshouldgetatleast35milestothegallonwhenit'snew. 21.Ifyouhaveastatedriver'slicense,_________. A.youcandriveanywhereintheU.S. B.youdon'thavetoapplyforaninternationaldriver'slicense C.Youcannotacrosstheborderinacar D.youmustknowthetrafficlawsofanotherstatebeforeyouenterit.
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