把行程时间缩短一半的方法
Zhangming and his father live in the countryside. One day, his father says, “Your uncle is sick. He needs this medicine. You must take it to him quickly. Your uncle lives in the town. It’s very far from here. You can ride a horse. It will take you two days to get there.” Zhangming says, “Don’t worry, Dad. I’m clever. I think I can get there in only one day.” Zhangming runs to the market and buys two horses for his journey (旅行).