英语翻译Transportation and communication networks bring people t

英语翻译
Transportation and communication networks bring people together.Yet sometimes people themselves create barriers(障碍) to transportation and communication.In some countries,laws stop people from moving freely from place to place.Over the centuries,many groups of people have been denied the freedom to travel because of their race,religion,or nationality.In the Middle Ages,for example,Jews were often forbidden to move about freely within certain cities.South Africa's government used to require black Africans to carry passes when they travel within the country.Some governments require all citizens to carry identification papers and to report to government officials whenever they move.
Countries set up customs posts at their borders.Foreign travellers must go through a customs inspection before they are allowed to travel in the country.Usually travellers have to carry special papers such as passports and visas(签证).Some countries even limit the number of visitors to their country each year.Others allow tourists to visit only certain areas of the country,or they may require that travellers be with an official guide at all times during their stay.
Many of those barriers to travel also act as barriers to communication.
When two governments disagree with each other on important matters,they usually do not want their citizens to exchange news or ideas freely.Countries often try to keep military or industrial information secret.
Today,people have the ability to travel,to communicate,and to transport goods more quickly and easily than ever before.Natural barriers that were difficult or dangerous to cross a hundred years ago can now be crossed easily.The barriers that people themselves make are not so easy to overcome.But in spite of all the different kinds of barriers,people continue to enjoy travel and the exchange of goods and ideas.
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交通和运输网络把人们汇聚到了一起.可是有的时候人们自己在交流和运输上面设置障碍.在一些国家,某些法律条文禁止人们从一个地方到另一个地方自由地迁徙.在好几个世纪以来,很多群人因为他们的种族、宗教和国籍被剥夺了旅游的自由.例如在中世纪,犹太人被禁止在某些城市里面自由地迁徙.南非政府曾经要求黑人在国境内旅游时要携带通行证.一些政府要求所有公民在迁徙时必须携带身份证和向当地政府官员汇报.
国家在它们的国境线上设置海关检查站.外国旅游者在被允许到这个国家之前先得通过一次海关检查.通常这些旅行者需要携带一些特殊的证件例如护照和签证.一些国家甚至限制每年到该国的旅游者的数量.还有一些国家只允许旅游者在该国特定区域游览,或者要求旅游者在该国居住期间身边随时配一名官方的向导.
那些旅游的障碍也扮演者交通障碍的角色.当两国政府在一些宏大问题上发生分歧时,他们通常不想让他们的国民自由地交换信息和观点.国家通常试图保守军事和工业信息的秘密.
现在,人们有旅游、交通、以及比以前更快捷更容易地运输货物的能力.在百年前很难很危险的天然障碍现在已经变得很容易通过了.人们自己制造的障碍不会那么轻易地克服.但是不管有各种各样的障碍,人们持续享受着旅游和交换货物和思维的兴趣.