Now the weather is getting cold, and the dog sleeps alone in the dog cage. Is it afraid of cold?

Of course, dogs are afraid of cold. It would be better if there is heating at home. Get a small quilt, fold it and spread it in a cage. If you are afraid of shit, lay half of it, and don't lay a quilt at the bottom of the other half of the cage. This is just right. Dogs don't get cold or poop. I wish your dog a healthy growth ~