Barter endured for thousands of years as the primary means of trade. Colonial powers forced bilateral barter upon their client states,making the colonies take expensive manufactured goods in return for bargain-price raw materials,and prohibiting them from trading with other nations. International trade was supposed to be freed from bartering's constraints in July 1944,when diplomats and economists attended the United Nations Monetary and Financial Conference at Bretton Woods,New Hampshire.
【正确答案】：易货贸易作为贸易的基本方式已持续了几千年。殖民列强强迫他们的附属国开展双边易货贸易，使殖民地国家用廉价的原材料换取昂贵的制成品，并禁止他们与其他国家开展贸易。1944年7月，外交人员和经济学家出席了在新罕布什尔州的布雷顿森林召开的联合国货币金融会议，要求国际贸易摆脱易货贸易的约束。
