photochemical fog

例句：

1. 1. The city was blanketed in a thick layer of photochemical fog on the morning commute.
   城市在早高峰时段被一层厚厚的光化学雾笼罩。
2. 2.The researchers found that the photochemical fog was caused by the emission of certain pollutants.
   研究人员发现，光化学雾是由某些污染物的排放引起的。
3. 3. The photochemical fog was so dense that it blocked out most of the sunlight and made it difficult for people to see clearly.
   光化学雾非常浓密，几乎遮蔽了大部分阳光，使得人们难以看清。