【正确答案】The United Nations is an international organization which was established after the Second World War and composed of sovereign states. Over the past half century, the United Nations has contributed much to realizing international security and peace. Following the Cold War, economics became a more influential factor in international relations. As the economic, trade and technological competition grows ever more fierce, the organization faces new tasks to further economic growth and social progress in developing countries, reduce the economic gap between the North and the South, and resolve the problems related to the environment, the control of population, refugee relocation, drug trafficking, etc.

【答案解析】
   1.第一句中，有两个“是”，第一个采用主系表的句式翻译，第二个采用which引导的定语从句。
   2.第二句中，“在……做出了巨大的贡献”翻译为contributed much to something，也可译为make great contributions to something。
   3.第四句中，前后两个分句存在因果关系，所以“由于”翻译为as来引导原因状语从句；“竞争空前激烈”译为competition grows ever more fierce；“解决诸如环境、人口控制、难民安置、贩毒等与发展相关的问题”翻译为resolve the problems related to the environment，the control of population，refugee relocation，drug trafficking，etc.。