Answer:
Man's most important invention.
What is something yet nothing, but if you fill it up it will disappear?
What can touch someone once and last them a lifetime?
They come in many varieties: Red, Black, Dead, and Caspian to name a few.
What gets broken without being hold?
Two little holes in the side of a hill. Just as you come to the cherry-red mill.
Easy
Animal
Difficult
Food
Funny
Kids
Logic
What am I?