世界各国被世界银行分为三大领域:高收人国家,中等收入国家和低收入国家。

世界各国被世界银行分为三大领域:高收人国家,中等收入国家和低收入国家。
【正确答案】：Countries of the world are divided by the World Bank into three categories of high-income , middle-income and low-income economies.