It sings at night when all other birds are asleep.
One night a bat comes and asks the bird why she is silent by day and sings only at night. The bird says,"When I am singing in the daytime, a man hears my voice, and I'm here now. So I don't sing in the daytime any more." But the bat says,"It is no use doing that now when you are a prisoner: you must do so before the man catches you ."的意思,谢谢