heavy fog大雾；
heavyadj.重的；沉的；(在数量、程度等方面)超出一般的；
fogn.雾；迷惘；困惑
The mountaineers found it hard to orient themselves in the fog.
登山者在大雾中很难辨认方向。
They were going to set off in the fog, but were dissuaded.
他们原打算在雾中出发，但被劝阻了。
It was a dangerous journey through thickening fog.
旅途中雾越来越大，险象环生。
