If your gums are turning black and have a cold sensation, I would suspect gingivitis or some other form of periodontal disease; in any event, this certainly should be examined by a dentist!
you say get cold feet . some people might say it's have cold feet , but for me , get cold feet makes more sense .
"Are your feet cold" is the correct way to phrase the question. It is asking about the current temperature of your feet. If you were asking about the temperature of someone else's feet, you would ask "Are your feet cold?"
100 feet
Your home air conditioner filter might be turning black because it is damp or moldy. It might also be turning black because it is filled with dust.
your feet are cold due to the temperature difference which exists between your feet and the tile. The cold sensation is felt as heat energy is transfer to the tile from your feet.
100 feet
the child has the fever but her hands and feet are cold
500 feet
10 feet.
He is turning into a werewolf. he was turning into a werewolf!
by turning the heating on.