Within a deep recess in the bulk of the time machine, a fog formed.
A black fog formed around our horses' fetlocks as we did.
Darkness had covered the switch of identities the first time; today, the fog formed the blanket.
The fog formed into spitting rain as the front finally arrived.
"Not until night, when perhaps fog will form in the lower reaches, and we can walk down that."
But more recently, a dense fog has formed around the company.
If the low level relative humidity rises towards 100 percent overnight, fog can form.
A fog formed in the space it had occupied.
The hangar's interior is so large that fog sometimes forms near the ceiling.
Max squinted, as though a fog had formed between Stan and himself.