Answer:
I'm white and used for cutting and grinding. When I'm damaged, humans usually remove or fill me. For most animals I am a useful tool. What am I?
I am an instrument capable of making numerous sound but cannot be touched or seen.
I have a head and a tail but no body. What am I?
A young man wants to have me but when he has me he no longer wants me. Blade in hand he attacks me and does his best to remove me. Yet he knows that it is all in vain.
I can bring tears to your eyes; resurrect the dead, make you smile, and reverse time. I form in an instant, but I last a life time. What am I?
No matter how little or how much you use me, you change me every month.