Answer:
I am needed for most animals and hardcover books. 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 asks but never answers?
I have a frame but no pictures. I have poles but not standing up. What am I?
What room do ghosts avoid?
Black we are and much admired. Many seek us if they are tired. We tire the horse, and comfort man, and turn White when we've fulfilled your plan.