smog、fog和haze这三个词的含义有什么区别？

smog、fog和haze这三个词的含义有什么区别？

(1) fog 即 a very thick mist，指「雾」，或「雾气」，例如﹕

London was famous for dense fogs. 伦敦曾以大雾闻名。 注 1﹕近几十年来，伦敦已少见大雾。 注 2﹕可用 bad、dense、heavy、thick 等字形容 fog，表示「大雾」或「浓雾」，但不可 说 big fog。

(2) haze 即 a very thin mist, especially caused by hot weather，指「烟雾」，或 「薄雾」，或「霾」，多由天气炎热所引起，例如﹕ The mountain was barely visible through the haze. 透过薄雾，该山仅隐约可见。

(3) smog﹕

smog 即 a haze caused by the effect of sunlight on foggy air that has been polluted by vehicle exhaust gases and industrial smoke，指「烟雾」，常由汽车 尾气和工厂烟尘所造成，属空气污染。