Davy wants to join the pet (宠物) club of his school, but he doesn't have a pet. What can he take to the club? It isn't easy for him to find a pet. One day, he sees a caterpillar (毛毛虫) in front of the classroom. It's small and green. Davy loves the caterpillar very much. "I will call you Caty，" says Davy. Davy takes his caterpillar to the pet club. Some children are talking about their pets.
"My dog can swim," says Bob.
"My cat can dance," says Jane.
"My bird (鸟) can sing with me," says Ray.
"My caterpillar can walk," says Davy.
But he can't find Caty. He looks for it everywhere. Where does Caty go? Davy doesn't look very happy. One day, he plays with his friends in the school. A butterfly (蝴蝶) stands on his head. Oh, it is Caty and it is back. It's now a butterfly.
