Answer:
What two things can always see what the other sees, but can never see each other?
At first, I am nothing. Add something to negate. Add again to oppose. Add again to find the time to draw. Add once more to find nobody at all.
Some live in me, some live on. And some shave me to stride upon. I rarely leave my native land. Until my death I always stand. High and low I may be found. Both above and below ground.
Who lives in a house with one bedroom, 50 hallways, and ghosts lurking everywhere?
What kind of room has no windows or doors?
Why was the cook arrested?