Answer:
What is it that after you take away the whole some still remains?
Draw fire or fill me; I'm still empty.
When you take away the whole from me there is always some left.
I am owned by the poor, the rich do not need me. If you eat me, you will die! What am I?
I saw the dead bring forth the living. I saw the living bring forth the dead. What did I see?
Though not a plant, has leaves. Though not a beast, has spine. Though many wouldn't need this thing, It's more valuable than wine.