Answer:
I am an instrument capable of making numerous sounds but cannot be touched or seen. What am I?
I don't live within a house, nor do I live without. Most will use me when they come in, and again when they go out. What am I?
What invention lets you look right through a wall?
Before I grow I'm small. When I'm old I grow tall. When I die I give a mighty fall.
I have a tongue, but cannot speak. I have a bed but cannot sleep. I have four legs but cannot walk. Yet I move as you do. What am I?
No matter how little or how much you use me, you change me every month.