Answer:
You use me between your head and your toes the more I work the thinner I grow.
What is easy to spot but hard to find?
I saw the dead bring forth the living. I saw the living bring forth the dead. What did I see?
My head and tail both equal are my middle slender as a bee. Whether I stand on head or heel Is quite the same to you or me. But if my head should be cut off the matter's true though passing strange directly I to nothing change.
What has four wheels and flies?
I flow from the Homerβs mouth when he sees doughnuts.