Answer:
Its days are numbered.
What object has keys that open no locks, space but no room, and you can enter but not go in?
No matter how little or how much you use me, you change me every month. What am I?
Where on earth do the ways always blow from the south?
What always comes into the house through the keyhole?
What did the piece of wood say when he saw the screwdriver and screws approaching?