Question: I give you a family of three:
One is sits down, and will never get up.
The second eats as much as is given to him, yet is always hungry.
The third goes away and will never return.
What are they?
Answer: Stove, fire, and smoke.
Question: My thickness is no more than a few centimeters, yet my depth can span to infinity. Although mundane, I intimidate most animals. When in my presence, you will inevitably follow me. What am I?
Answer: I'm a mirror.