Mr. Smith and Mrs. Smith have a son. His name is Jack. Jack is only three years old. He is very lovely, and he always asks his parents questions.

One day, Mr. Smith is reading a book on the sofa in his room. And he has a banana in his hand. He likes to eat a banana while reading. Jack comes in. He looks at the banana in Mr. Smith's hand and asks," Dad, what's this?" But Mr. Smith doesn't hear him, so he doesn't answer him. Then Jack goes up to Mr. Smith, shakes (摇动) his leg and asks, "What's this, Dad?" "It's a leg," answers Mr. Smith. Then Jack goes out of the room and says to Mrs. Smith, "Mum, I want to eat a leg." After that, his parents laugh happily.