Ghosts press the bed, dreaming of cats.

I've had it before. Feudalism is commonly known as ghost pressing bed. Although there is some truth, it is scientifically understood that people are overtired and nervous, which is roughly like dreaming. But you can feel the outside world, and even hear people talking, and you may feel terrible. It varies from person to person. In fact, as long as you have a regular schedule, supplement some nutrition, and drink some milk before going to bed, you won't recover your body function. In the last two or three years.