Answer:
What has one eye but cannot see?
Hard to catch, easy to hold. Can't be seen, unless it's cold.
What has 13 hearts but none beat?
One by one we fall from heaven down into the depths of past, And our world is ever upturned so that yet some time we’ll last.
I can move even when you are still. I can be one or many.
What did the piece of wood say when he saw the screwdriver and screws approaching?