答案部分：

　　Section 1: 英译汉

　　农业的重要性怎样强调都不为过。世界百分之五十以上的劳动力从事农业。二十世纪八十年代初，农业劳动力的比例在非洲高达百分之六十七，在北美洲则不足百分之五，在西欧约为百分之十六，在东欧和苏联约为百分之三十二，在亚洲则约为百分之六十八。

　　农场规模因地而异，差别很大。直到最近，加拿大农场的规模平均约为186公顷(约合460英亩)，美国农场的规模约为175公顷(约合432英亩)。但在菲律宾，私人农场的规模平均略少于3.6公顷(不足9英亩)，在印度尼西亚则略少于 1.2公顷(不足3英亩)。

　　农场的规模还取决于其用途。大农场通常从事商业耕种，或者说为赚钱而生产。拉丁美洲的大庄园就是大片的私有土地，雇人劳动。单一作物的种植园生产茶叶，橡胶或可可。生产小麦的农场最有效益。它们拥有几千公顷土地，雇佣一群群工人，并使用机器。澳大利亚牧羊场和其它畜牧场的规模一定要大到足以能为成千的牲畜提供充足的饲料。

　　零散的维持生计的个体农场，或者说混合经营的小规模家庭农场，在发达国家已日渐减少，但在非洲和亚洲的发展中国家里仍大量存在。美国的“返回田地”运动扭转了1970至1980这十年间新英格兰和阿拉斯加小农场衰败的局面。

　　一个地区究竟生产什么取决于它的气候、供水、地形和其它条件。

　　自有农业以来的一万多年中，各地的人们发现了野生动植物的食用价值，于是将其加以驯化或栽培，最重要的是谷物，如小麦、稻子、大麦，玉米和黑麦。

　　农业收入还来自非粮食作物，如橡胶、纤维植物、烟草以及可用于生产化学合成品的油料作物。此外;还可通过饲养动物取其皮毛而获利。

　　一个国家赚取的外汇，很大一部分可能来自某种单一的商品。例如，斯里兰卡依靠茶叶，丹麦专门经营奶制品，澳大利亚出口羊毛，新西兰和阿根廷则出口肉类制品。在美国，近年来小麦已成为其赚取外汇的主要商品。

　　一个国家是否以出口农产品为主取决于许多可变因素。其中一个因素就是这个国家的工业可能很不发达，无法生产足够数量和技术先进的工业品。这类农产品出口国包括加纳，出口可可，还有缅甸，出口大米。另一方面，特别发达的国家可能生产过剩，大于本国人的需求，美国、加拿大和一部分西欧国家就是这种情况。

　　Section 2: 汉译英

　　Tibet, located on the "Roof of the World", is still an underdeveloped area in China because of its harsh natural conditions and various social and historical restrictions formed by centuries of backward feudal serfdom. However, the development of Tibet in the past 50 years has greatly changed its former poor and backward look, and the Tibetan people's living standards have greatly improved. Social and economic development has enriched the people's material and cultural life remarkably. In 2000, people of various ethnic groups in Tibet basically shook off poverty, and had enough to eat and wear. Some of them began to live a better-off life. Along with the improvement in the people's livelihood, consumer goods such as refrigerators, color TV sets, washing machines, motorcycles and wristwatches have entered more and more ordinary homes. Many well-off farmers and herdsmen have built new houses. Some have even bought automobiles. Currently, Tibet ranks first in per-capita housing in the country. Radio, television, telecommunications, the Internet and other modem information transmission means are now part of daily life in Tibet. News about various parts of the country and the world now reach most people in Tibet by radio and TV. Local people can obtain information from and make contacts with other parts of the country and the world through telephone, telegram, fax or the Internet. The Tibetan people's health has also improved substantially, because the situation featuring a lack of both doctors and medicine has changed fundamentally. The average life expectancy of the Tibetan people has increased from 35.5 years in the 1950s to 67 years presently.