This paper discussed the principle of externality in the domain of urban wastewater reuse, analyzing the external economy of urban wastewater Reuse with the theory of economics.是什么意思_This paper discussed the principle of externality in the domain of urban wastewater reuse, analyzing the external economy of urban wastewater Reuse with the theory of economics.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句