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car-pool metropolitan overcrowding collision car accident density of population overpass underpass internal combustion engine diesel engine steam-driven petrol-driven hydrogen-driven chaotic horse-drawn carriage chariot
拼车 n.&vi. car-pool 大都市的 adj. metropolitan 过度拥挤 n. overcrowding 撞车 n. collision/ car accident 人口密度 density of population 高架桥，过街天桥 n. overpass 地下过街通道 n. underpass 内燃机 internal combustion engine 柴油机 n. diesel engine chaotic 蒸汽驱动的 adj. steam-driven 汽油驱动的 adj. petrol-driven 以氢气为动力的 adj. hydrogen-driven 混乱的 adj. chaotic 马拉的观光车 horse-drawn carriage 欧洲古代的战车 n. chariot