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第三个空需要根据上下文判断才能填上说详细点。还有，上文要几句，下文要几句。不看完形填空的原题我怎么会知道Wehavetwoclassroombuildingsinourschool.Amongthebuildings,thereisaplayground.Wecanplaythere.Intwobuildings,therearemanyclassrooms,twomusicrooms,twocomputerroomsandmanyoffices.Ourteachersarealwaysverybusy.Theyareverykind,too.OnthesecondfloorofSonthBuilding,thereisa_____.Therearealotofbooksinit.library 因为下文说它里面有很多书