When collateral is sold, Dai used to cover the debt is destroyed.
This is to keep the system balanced, so all Dai in circulation is still overcollateralized in USD value, the Maker Protocol will be able to meet its financial obligations, and the system will be healthy.
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当抵押物被出售时，用于偿还债务的Dai被销毁。
这是为了保持系统平衡，因此流通中的所有Dai仍以美元价值过度抵押，制造商协议将能够履行其财务义务，系统将保持健康。
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