Answer:
What do you fill with empty hands?
Something wholly unreal, yet seems real to I. Think my friend, tell me where does it lie?
You heart it speak, for it has a hard tongue. But it cannot breathe, for it has not a lung.
What kind of nut is empty at the center and has no shell.
By Moon or by Sun, I shall be found. Yet I am undone, if there's no light around.
You use it between your head and your toes, the more it works the thinner it grows.
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?