exchange of commodities

例句：

1. 1.They exchanged their stories for a cup of coffee.
   他们用一杯咖啡换故事。
2. 2. The company exchanges its products with other companies for raw materials.
   这家公司与其他公司交换产品以获取原材料。
3. 3. Exchange rates fluctuate daily due to fluctuations in the global economy.
   由于全球经济的波动，汇率每天都会变动。