The urban rail transit systems of Berlin and Cologne in Germany are introduced, and some experience in the planning, design and operation of urban rail transit system is summarized.是什么意思_The urban rail transit systems of Berlin and Cologne in Germany are introduced, and some experience in the planning, design and operation of urban rail transit system is summarized.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句