Answer:
A girl is sitting in a house at night that has no lights on at all. There is no lamp, no candle, nothing. Yet she is reading. How?
What always comes into a house through the keyhole?
What goes up the hill and down the hill, And spite of all, yet stand still?
What is as big as you are and yet does not weigh anything?
How can you place a pencil on the floor so that no one can jump over it?
Not born, but from a Mother's body drawn. I hang until half of me is gone. I sleep in a cave until I grow old. Then valued for my hardened gold.