Preliminary Research of Mountainous Slope Land Ecological Stability and Sustainable Economical Development Study in the First Sub-Region of Gullied Rolling Loess Region是什麼意思_Preliminary Research of Mountainous Slope Land Ecological Stability and Sustainable Economical Development Study in the First Sub-Region of Gullied Rolling Loess Region在線翻譯_英語_讀音_用法_例句