Answer:
Name for zenith
No matter how little or how much you use me, you change me every month.
My tongue hangs out as I run over fields and streets all day. I get tied up every morning and untied at night.
I know a word of letters three. Add two, and fewer there will be!
A hill full, a hole full, yet you cannot catch a bowl full.
What is so fragile that saying its name breaks it?
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?