pollution-free的用法和样例：
例句
- Respirators should only be removed when the wearer is in an area that is considered free of airborne hazards, including confirmed or suspected influenza patients.
呼吸防护口罩只能在无污染的环境中，包括无确诊或疑似流感病人的环境中摘除。
词汇搭配
- pollution-free fuel 无污染燃料
- pollution free technology 无污染工艺
- pollution-free energy 无污染能源
- pollution-free engine 无污染发动机...
