Answer:
If you happen to wake up at dawn, you'll probably find this covering the lawn.
What is something yet nothing, but if you fill it up it will disappear?
What goes trough your head but you forget it like 3 days after?
What gets broken without being hold?
They come out at night without being called, and are lost in the day without being stolen. What are they?
What never gets any wetter no matter how hard it rains?