On the Regeneration of Ecological Environment in Spatial Expansion of the Valley Cities in West China--A Case Study about Construction of New Yuzhong Urban Area in Lanzhou是什麼意思_On the Regeneration of Ecological Environment in Spatial Expansion of the Valley Cities in West China--A Case Study about Construction of New Yuzhong Urban Area in Lanzhou在線翻譯_英語_讀音_用法_例句