smogs的音标：...

New York City has had several London - type smogs since 1950.自1950年以来,纽约市发生过几次伦敦 式 的烟雾.Killer smogs don't happen very often, fortunately.幸亏致人死命的烟雾不常出现....

n.烟雾( smog的名词复数 )...