Today, we know that some gases such as O3, carbon monoxide, nitric oxide and carbon dioxide can have dual actions, behaving either as useful or as harmful agents.是什么意思_Today, we know that some gases such as O3, carbon monoxide, nitric oxide and carbon dioxide can have dual actions, behaving either as useful or as harmful agents.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句