since the 1940s, southern California has had a reputation for smog.
2018年6月四級真題（第二套）閱讀 Section A
A few hours before, I'd been at home in Hong gonk, with its choking smog.
2015年高考英語全國卷1 語法填空 原文
If the air you're breathing is clean—which it would be if you're away from the smog of cities—then the air is filled with life-giving, energizing oxygen.