Answer:
What gets sharper the more you use it?
I have three heads. Cut off one I become stronger. Cut off two I become ten.
I have cities with no people, forests with no trees, and oceans with no water. What am I?
Although a human shape I wear, mother I never had. By every miss I'm valued much, still my cruel fate is such by boys I am often despised. What am I?
I am rarely touched but often held. If you are smart you'll use me well. What am I?
The sun bakes them, The hand breaks them, The foot treads on them, And the mouth tastes them. What are they?