Flagsarenowseeneveryday,buttheywereonceonlyusedinbattle...
問題詳情：Flagsarenowseeneveryday,buttheywereonceonlyusedinbattles.Nooneknowsforsure___61___flagscamefrom.However,itseemsthatChinaandtheRomanEmpirewerethefirstonestousethemtoidentifytheirarmies.The___62...