Answer:
What is put on a table cut but never eaten?
I spend the day at the window, go to the table for meals, and hide at night. What am I?
What is the beginning of eternity the end of time and space the beginning of every end and the end of every race?
I am easy to waste and unstoppable. What am I?
lighter than feather and softer than silk yet the strongest man in the world cannot hold me for more than a few minutes.
No matter how little or how much you use me, you change me every month.