In the middle of a dark forest, there lives an owl . All the animals know that he is the wisest  among all of them. So they often go to him and tell him their troubles. Then the owl always teaches them what they should do. One day, a little bird goes up to the owl. She is crying. "what's wrong with you?" asks the owl. "I'm not happy at all. I don't want to be a bird," the bird says. "Why don't you want to be a bird?" asks the owl. "I am so small, weak and useless," she cries. "I want to be big and strong like the lion. He is very important, but I am not" Then the owl whispers  something in her ear. At once the bird dries her _ and goes away. One week later, the bird came back. "Oh, thank you very much. You are a very wise owl," she says to the owl. "I am very happy now. Every day, I sit on top of the tallest tree and watch for  lions and tigers. When they come near, I shout at the top of my voice. Then my friend all run and hide. They are very thankful to me. I am useful and important now" The wise owl smiles and says, "No one in this world is useless." From the story we know   _  .
the bird's friends are very thankful to her because she drives the tigers and lions away the lions and tigers run away when they hear the bird's voice the bird thinks that she is useful and important now the owl is useless.