Answer:
I wiggle and cannot see; sometimes underground and sometimes on a tree. I really don't want to be on a hook and I become a person when combined with “book”.
Two in a whole and four in a pair. Six in a trio you see. Eight's a quartet but what you must get is the name that fits just one of me.
I am what one cannot keep, two cannot hold, and three cannot destroy. What am I?
I am drawn by everyone without pen or pencil
I am heavy forward but backward I am not. What am I?
No matter how little or how much you use me, you change me every month.
What am I?
Animal
Difficult
Easy
Food
Funny
Kids
Logic