The companionship of a backpack is irreplaceable. From the innocence and innocence of our elementary school years, to the youthful vigor of our middle school years, and to the maturity and stability of our university years, backpacks have always silently accompanied us. It witnesses our growth and progress, and also carries our dreams and hopes. Whenever we encounter difficulties in learning, we can feel the power of knowledge and the courage to move forward by looking at the heavy books and materials in our backpacks.