Once upon a time, there were two puppies, one named Pippi and the other named Bibi. Pippi was serious in class and Bibi was playful in class. One day they met.
One day, Pippi went to buy candies, and Bibi also went to buy candies. By coincidence, they met in the candy store at the same time. Pippi said to Bibi: "It's really funny that you are so short and you come here to buy candies." "I should say this to you
said, "The two puppies raised their heads very high. Pipi had an idea and said to Bibi: "Then do you dare to compete with me to see who is taller?" "Competition, who is afraid of whom!" Bibi shouted, and after saying that, they ran towards the haha mirror not far away.
Pippi knows that concave lens can make itself bigger, and convex lens can make itself smaller, so Pippi stood in front of the concave lens, and there was no doubt that Bibi stood in front of the convex lens. Pippi saw that her body was almost twice as big as her original size, and she secretly rejoiced in her heart. When she looked at Bibi, she found that it was small. The body was not as big as that of a mouse, and Bibi looked up at Pippi, feeling frightened and running away without a trace.
Another day, Bibi went for a walk and met Pippi again. She was trembling with fear and hated her parents for not giving her two more legs. Bibi said: "Who are you? I don't know you. I ran away after saying that." Haha, Bibi is really timid, Pippi said with a smile.
