“地下通衢肇始燕,铁流暗涌古城隧。北畅南达东西贯,京都沧桑变繁华。”这形容的便是北京地铁。地铁,英文名为subway,是现代化城市标志之一,因其快捷、舒适、能耗低、污染少、方便,已成为城市公共交通的主干线。每天生活在这个国际化的大都市,地铁是我们经常使用的交通工具之一,这个高科技产物,我 “Underground thoroughfare begins to Yan, iron submerged ancient city tunnel.North Changnan east and west, Kyoto vicissitudes of life become bustling.” This describes the Beijing subway. Subway, the English name is subway, is one of the modern city signs, because of its fast, comfortable, low energy consumption, less pollution, convenience, has become the main trunk of urban public transport. Living in this cosmopolitan city every day, the subway is one of the transportation tools we often use, this high-tech product, I