What is the difference between "stay asleep" and "stay sleep"?
If we are talking about the act of continuing to sleep, only "stay asleep" or "stay sleeping" are appropriate. "Stay sleep" is grammatically incorrect, so "stay sleeping" should be used instead. The most natural expression is "stay asleep." Ex: I sleep so deeply, I can stay asleep even through a hurricane. Ex: I sleep so deeply, I can stay sleeping even through a hurricane.