1.   A thick fog descended and I knew that we were in grave danger.

2.   A thick fog descended on the mountain, and I knew that we were in grave danger.

3.   As bad luck would have it, there was a thick fog the next day and our flight was delayed.

4.   By the time we reached the island, dusk was falling and a thick fog had rolled in.

5.   He was walking home in a thick fog, wondering when the crisp, blue skies of autumn might appear.

6.   I locked up the office and walked out of the student center into a thick fog.

7.   It was a warm day when I saw a thick white fog gradually creeping up the sides of the hills.

8.   On another memorable night, coming home in a thick fog Jimmy got us completely lost.

9.   Owing to the thick fog all day long, we had to take extra precautions on the road parts of the walk.

10.   Perhaps it was exhausted, perhaps it had lost its bearings in the thick fog.