布莱克先生的创意门洞：为大小猫咪量身打造
Mr Black has two cats. One is big and the other is small. He likes them very much. One day his friend Mr Green comes to see him. He is very surprised. He finds there are two holes in the door, a big hole and a small hole. “My dear friend, why are there two holes?” asks his friend. “How can the big cat go through the small hole?” he says.