Mamma Cat
More information would be helpful. But, cats normally breathe through their nose and don't like to breathe through their mouths. So I am assuming that your cat has a blocked nostril.
Get some normal saline (little noses for infants is great) and squirt it in the nostrils. No, your cat won't like it, but it will open the nasal passages. Also, add a humidifier to your cats room. It is winter and the air inside is very dry which will contribute to a blocked nostril.
melissa
Get ur cat to a vet or animal hospital asap . If the kitty is barely breathing their might be something seriosely wrong