voluntary association

基本解释

A free enterprise economy is based on the principle of voluntary association and exchange.
私有经济的基础是自发联合和交换。
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The International Air Transport Association (IATA) is a voluntary association of international airlines that sets routes, fares and other standards of service.
国际航空运输协会（IATA）是国际航空公司自发组织的协会，负责设定线路，制定票价，和其它服务标准。
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The American flag, on the moon or anywhere else, is worthless except as a symbol, a symbol of men achieving their ends by voluntary association, cooperating through mutual exchange in a free society.
不管是在月球上，还是其它任何地方，美国的旗帜除了代表着人们在自由市场，通过自愿联合，相互合作的方式来实现各自的目标外，一钱不值。

The pioneers on the frontier developed organic, local community governance through voluntary association.
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That is, us, ourselves, in voluntary association, getting to grips with the errors and omissions of the universe around us.
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Libertarians are correct that much common good could be accomplished by voluntary association without the heavy hand of corruptible politicians.
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