Answer:
What is it that no man ever saw, which never was, but always will be?
What hangs in the sky by day but at night goes away?
It is a form of plastic money.
Power enough to smash ships and crush roofs. Yet it still must fear the sun.
Proof you've done your time in school
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.