练习1、首先找出主题句，然后排列各句：1.a.Computersspeedupregistrationbyprovidingup-to-dateinformationonopenclasses.b.Theyassistinstructorsbymarkingmultiple-choicetests.c.Computersnowperformmanytasksonmycampus.d.Computerscansupplyadvisorswithinstantandcompleteinformationonrequirements,careerinformation,andpersonaldatawhiletheyaretalkingtoastudent.e.Computerskeeprecordsforthebookstore,library,cafeteria,andmaintenancedepartment.第30页，共86页，星期日，2025年，2月5日2.a.MynewFuturecamerahasseveralfeaturesthatIlike.b.Itadvancesthefilmaftereachshotandautomaticallyrewindsitaftereachroll.c.Comparedtoothercameras,itisinexpensive.d.IfIgettooclosetothesubject,italertsmewithabuzzer.e.Itbeamsoutaninfraredraythatfocusesforme,eveninthedark.f.Itislightweightandcompact.第31页，共86页，星期日，2025年，2月5日3.a.Sometimesrapidly,sometimesslowly,theywentrelentlesslyupward.b.LastweektheLaborDepartmentreported,however,thattheeconomy’sseventeen-yearinflationaryspiralhad,foronemonthatleast,finallybeenbroken.c.DuringMarch,inflationactuallywentdowninsteadofup.d.Thisturnedatrendofwhateconomistscalldisinflationintooutrightdeflation.e.Since1965,pricesintheU.S.economyhavebeenheadingoneway.第32页，共86页，星期日，2025年，2月5日4.a.Movingbackhomewithhisparentswouldsavehimquiteabit.b.Hewasgladthathenolongerhadtoworkfull-timewhilegoingtoschool.c.Hisincometaxrefundwasenoughtocoverhisexpensesfortherestofthesemester.d.Thedean’sofficeapprovedhisstudentloan,andhecouldcuthisworkinghours.e.Hehadfinallypaidoffhiscar.f.Thingswerebeginningtolookup.第33页，共86页，星期日，2025年，2月5日5.a.TwoyounggirlstookturnsthrowingtheirFrisbeetotheirdog,whichleapedintotheairtocatchit.b.Afamilyoftouristsstoodinfrontofthefountain,studyingamapandtryingtorememberwheretheyha