Urban rail transit has the characteristics of large freight volume, fast, safety and less environmental pollution.

城市轨道交通具有运量大、速度快、安全性高和环境污染低等特点。

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Urban rail transit has the characteristics of large freight volume, fast, safety and less environmental pollution.

城市轨道交通具有运量大、速度快、安全性高和环境污染低等特点。

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