1. Books are ladders-Gorky said, "Books are ladders for human progress."

2. Books are nourishment-Shakespeare said, "Books are nourishment all over the world."

3. Books are the source-Gorky said, "Take care of books, they are the source of knowledge."

4. Books are good medicine-Liu Xiang (China, a great scholar in the Han Dynasty) said: "Books are still medicine, and good reading can cure fools."

5. Books are society-Pirogov said: "A good book is a good society, which can cultivate people's feelings and temperament and make people noble."