cost- efficient city

• 节约型城市

cost- efficient city的用法和样例：

例句

1. The city gleans and collects scraps people contribute to development of circulation type city society, while they also bring a series of social problems of city administration.
   城市拾荒者在为循环型城市社会的发展做出贡献的同时，也给城市管理带来了一系列的社会问题。