A bird was confined in a cage outside a window. She often sang at night when all other birds were asleep.
One night a bat came. He asked the bird why she was silent by day and sang only at night.
The bird answered, “Last year when I was singing in the daytime, a bird catcher heard my voice and caught me in his net.Since then I have never sung by day.”
The bat replied, "But it is useless to do this now that you have become a prisoner." Then he flew away.