Answer:
Whoever makes it, tells it not. Whoever takes it, knows it not. Whoever knows it, wants it not. What is it?
Two brothers we are, great burdens we bear. All day we are bitterly pressed. Yet this I will say, we are full all the day, and empty when go to rest.
What turns everything around but does not move?
What travels from house to house and is sometimes narrow and sometimes wide but always stays outside?
Everyone has it and no one can lose it, what is it?
What is lighter than what it is made of?