国家与国家之间的界限叫国界线。在国界线上,会有很多的界碑,作为相邻两国之间界限的标志。世界上的国界线千千万万种,有的形同虚设,有的严防死守,有的任意通行,有的天壤相隔。下面是一些有趣的国界线,哪一种让你脑洞大开了呢?美国和墨西哥:国界两边打排球美国亚利桑那州纳科的居民和墨西哥纳科的居民,每年都会在国界两边打一场排球赛。 The boundary between countries is called the national boundary. On the national front, there will be many border palaces as a sign of the boundaries between neighboring countries. There are thousands of national boundaries in the world, some of which are non-existent, some of them guard against sticking to the ground and others pass freely, some of which are far apart. The following are some interesting national boundaries, which kind of let you open your mind? United States and Mexico: playing volleyball on both sides of the border Nationalities residents of Nacot Arizona and Mexico Nac, a fight each year on both sides of the border Volleyball match.