Answer:
What is it that no man ever saw, which never was, but always will be?
A beautiful succession of sounds.
I cannot be felt, seen or touched; Yet I can be found in everybody; My existence is always in debate; Yet there is a style of music named after me.
What do you have in December that you don't have in any other month?
What has a hundred limbs, sometimes leaves, but cannot walk?
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.