_________(污染）air does harm to our health,it's necessary to keep air fresh and clean
问题描述：
_________(污染）air does harm to our health,it's necessary to keep air fresh and clean
答
contaminated,被污染的.
规范的科技文献中polluted一词很少用,通常用作名词,如air pollution control,water pollution management 等.
仅供参考.
祝好