fogs
When there is fog, there are tiny drops of water in the air which form a thick cloud and make it difficult to see things.
The crash happened in thick fog.
这次撞车发生在浓雾中。
A fog is an unpleasant cloud of something such as smoke inside a building or room.
a fog of stale cigarette smoke.
一团难闻的香烟烟雾。