假设欧洲货币体系成为了一个使用统一货币的货币联盟，却没有设立一个欧洲中央银行来管理统一的货币。相反，它

允许各国中央银行自己发行并管理这种货币：各国愿意发行多少这种货币就可以发行多少。并且可以进行公开市场操作。你能否预测这将会产生什么问题？

Imagine that the EMS became a monetary union with a single currency but that it created no European Central Bank to manage this currency．Instead，imagine that the task was left to the various national central banks．each of which was allowed to issue as much of the European currency as it liked and to conduct open-market operations．What problems can you foresee arising from such a scheme？