1. 雾
    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.

    e.g. The crash happened in thick fog...
           浓雾中发生了撞车。
    e.g. These ocean fogs can last for days.
           这种海上大雾可持续数天。

2. 烟雾;尘雾
    A fog is an unpleasant cloud of something such as smoke inside a building or room.

    e.g. ...a fog of stale cigarette smoke.
           一股难闻的香烟烟雾

3. 迷惑;迷雾
    You can use fog to refer to a situation which stops people from being able to notice things, understand things, or think clearly.

fog的解释

    e.g. The most basic facts about him are lost in a fog of mythology...
           关于他的那些最基本信息离奇地湮没无踪了。
    e.g. Synchronizing these attacks may be difficult in the fog of war...
           在迷雾一样的战争中可能很难同时发动这些攻击。

4. (使)(窗户、镜子等)起雾;(使)变模糊
    If a window, mirror, or other glass surface fogs or is fogged, it becomes covered with very small drops of water so that you cannot see things clearly through it or in it.

    e.g. The windows fogged immediately...
           窗户立刻被雾气笼罩了。
    e.g. Water had fogged his diving mask and he couldn't remember how to clear it...
           水的雾气模糊了他的潜水镜，他却不记得该怎样除雾了。