Sailorsusedtospeakofa“Jack”whentheymeantaflagwhichwasse...
问题详情：Sailorsusedtospeakofa“Jack”whentheymeantaflagwhichwassetnearthebowofasailingship.Theflagshowedthecountrytowhichtheshipbelonged.TheUnionJackbecametheflagofGreatBritain.Australia'sflaghastheU...