noun 下载 🔗分享 边境,边界。 The part of a country which borders or faces another country or unsettled region Examples : ""The soldiers guarded the country's frontiers against any possible invasion from neighboring nations." " 士兵们守卫着国家的边境,以防邻国可能的入侵。 geography nation area politics state 与AI对话词汇游戏阅读练习
noun 下载 🔗分享 前沿, 前线 The most advanced or recent version of something; leading edge. Examples : "the frontier of civilization" 文明的前沿 technology science achievement 与AI对话词汇游戏阅读练习
noun 下载 🔗分享 前沿阵地,前哨阵地 An outwork of a fortification. Examples : "The soldiers patrolled the frontiers of the castle's outer wall, watching for enemy movements. " 士兵们在城堡外墙的前沿阵地巡逻,警惕地观察敌人的动向。 military architecture war 与AI对话词汇游戏阅读练习