Answer:
I am between earth and heaven. What am I?
I am round as an apple, deep as a cup. All the King's horses can't pull me up. What am I?
I can be in your body but never on your placemat. I'm always better when I'm fresh, but you'll never see me in the flesh. What am I?
I run smoother than any rhyme I love to fall but cannot climb.
By Moon or by Sun, I shall be found. Yet, if there's no light around, I am undone. What am I?
Whoever made me don't want me. Whoever bought me don't need me. Whoever use me don't know me.