《國際商務(wù)概論》：

　　The three types of economies are closely related to the political systems of the nations.Free enterprise economies are ones where the govemment almost has no control The trade， and industry are largely run by private firms.The best example of this type is the United States of America.In addition， some other countries that have mixed economies are getting closer and closer to free enterprise by means of privatization. 

　　Mixed economies are ones where different types of economies exist side hy side.In mixed economies there are industries that are run by the state， but a large number of industries and most trading activities are controlled hy private firms.The best examples are the countries of the European Union （ EU）.Many advanced nations and developing nations also have some state—run industries. 

　　Controlled economies are ones where the government controls the whole economy.Besides， the trading activities are also controlled by the govemment.China used to be of this type of economy. 

　　In a way， we may say all economies are mixed economies with some differences in the extent to which the economies are mixed.This is because mixed economies have the advantages of controlled economies and free enterprise economies but avoid their respective disadvantages.

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