Unit1The Evolution of Transport交通工具的演化
The evolution of transport has been closely linked to the development of humankind throughout the earth’s history．Transport’s early function was to meet the basic need of hauling food supplies and building materials．But with the formation of tribes，then peoples，and finally nations，the societal and economic functions of transport became more and more complex. At first there was mobility required for individuals，clans，households，and animals to protect them against，and to escape from，the dangers of natural disasters and tribal aggressions，and in the search for the best places to settle．As tribal groups formed and gradually established their geographical identity，transport was increasingly needed to open up regions for development，to provide access to natural resources，to promote intercommunal trade，and to mobilize territorial defense．When the first nations came into being，transport played a major role in establishing national integrity．
交通工具的演变紧密相连的人类在整个地球的历史发展。运输署早期功能是满足基本需要搬运粮食供应和建材等领域。但随着部落，然后人民，和最后国家形成，运输的社会和经济功能变得越来越复杂。在第一次有流动性所需的个人、宗族、家庭和动物保护他们免遭，和逃避危险自然灾害和部落的侵略行为，并在寻找最好的地方定居。部落群体形成和逐步确立其地理特征，运输日益需要开放地区的发展，以提供对天然资源，促进族裔间的贸易，并调动本土防卫的访问。当第一次的联合国应运而生时，运输发挥了重要的作用，建立民族气节
After basic societal needs had generally been attended to，local communities could increasingly devote their efforts to enhancing their economic，cultural，and technological development through trade links with other peoples and regions．Again，transport provided the mobility required for such intertribal, international，and finally intercontinental cultural exchange and trade．During all of this gradual development toward an organized human society，represented today through the international family of nations，transport as physical process of moving people and goods，thus promoting such development，continuously underwent technological and organizational changes．Such changes were induced by several factors and circumstances．In fact，today’s transport in its various forms and organizational arrangements remains highly subject to changes in response to societal requirements and preferences．
基本社会需求大体上已照顾到后，当地社区可能会越来越多地致力于加强贸易联系通过与其他民族和地区经济、文化和科技发展共同。再次，运输提供所需的这种部落之间、国际和洲际最后的文化交流和贸易的流动。在所有有组织的人类社会，今天代表国际大家庭，交通工具的移动人员和货物，物理过程，从而促进这种发展，通过向此逐步发展的过程中不断发生了技术和组织的变化。这种变化是几个因素及环境所致。事实上，今天的各种形式和组织安排运输仍高度受回应社会需求和偏好的变化。
Clearly，the first and foremost criterion to be satisfied by transport was efficiency．For centuries，and particularly during the takeoff stages of local economics，society required reliable，fast，and low cost transport．The search for appropriate technologies was relatively unconstrained．There were times in human history when the demand for reliable and fast transport was especially pronounced，and quick solutions were required for national self-defense. During such periods of local and international conflict, human ingenuity devised new transport technologies which often proved to be the decisive element for survival, and
