烟霾

例句：

1. 1. The city iscovered in a thick layer of smog from the factory.
   这座城市被工厂的浓雾覆盖。
2. 2. The air quality has significantlyimproved since the government implemented stricter pollutioncontrol measures.
   自从政府实施了更严格的污染控制措施后，空气质量已经显著改善。
3. 3. During the morning rush hour, thestreets are often filled with people struggling tobreathe through the heavy smog.
   在早高峰时段，街道上常常挤满了努力呼吸通过浓雾的人群。