箱子太重？看看这位男子怎么做的吧！
Look at this man. What is he doing? He’s carrying a very big box. The box is full of big apples. He wants to put it on the back of his bike and take it home. Can he do that? No, I don’t think so. Why not? Because the box is too full and too heavy. Look! What’s wrong? He drops the box. Poor man!