Although it exists in the embryonic form in China, the complementary currency can be seen in only a limited number of fields, whose function has not been brought into the full play.

在中国虽然也有补充货币的雏形，但涉及范围还很小，也没有充分发挥其补充货币的作用。

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As a supplement form of official currency, the complementary currency is different from the official currency in that the former does not generate interests and inflation.

补充货币作为官方货币的补充形式，以不计利息，不产生通货膨胀的特征区别于官方货币。

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The most easily recognized complementary currency is frequent flyer miles, now issued by 92 airlines.

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Paul Glover, the founder of the Ithaca Hours complementary currency for use in Ithaca, New York, has been bombarded with requests to help set up local currencies around the country.

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They call these complementary or cooperative rather than competing currencies because they are not competing to replace the official currency, but to complement it where it is leaving available resources unused.

FORBES: Rethinking Money: The Rise Of Hayek's Private Competing Currencies