（In the past few days differences between the United States and the European Community on farm trade have narrowed almost to nothing. As a result the world is now close to concluding the Uruguay round of GATT talks. That deal is admittedly far from perfect, a series of messy compromises. The cause of free trade will have many more battles to fight. Never mind. On a conservative estimate the Uruguay round would permanently raise global welfare by more than $ 100 billion a year, spur economic growth everywhere (especially in the world’s poorest countries) and extend competition to hitherto sheltered, and therefore backward, parts of all economies. By any standards, it would be a hugely valuable achievement.）Why would an economy be backward once it is “sheltered”?
【正确答案】：When one country’s economy is “sheltered” and with little competition, it is most difficult for them to make good use of their absolute and comparative advantages, leaving the country far behind in economic development.
