negative external issues

• 负外部性

negative external issues的用法和样例：

例句

1. Renting in groups refers to the housing phenomenon of living crowded and having bigger negative externalities.
   群租是指居住拥挤并产生较大负外部性效应的居住现象。
2. Some NTBS may restrict trade but improve welfare in the presence of negative externalities or informational asymmetries.
   一些非关税壁垒可能会限制贸易，而是改善福利，在存在负外部性或信息的不对称性。