Answer:
From house to house I go, sometimes narrow, sometimes wide. Whether there's rain or snow, I always stay outside. What am I?
I am a ship that can be made to ride the greatest waves. I am not built by objects, but built by minds. What am I?
It's in your hand though you can not feel it. Only you and time can reveal it.
What goes through towns and over hills but never moves?
What force and strength cannot get through, I with my unique teeth can do. What am I?
No matter how little or how much you use me, you change me every month.