Required reserve is compulsory and must be observed unconditionally.

准备金是强制性的，必须无条件地遵守。

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The proportion that financial institutions' excess reserve accounts for its total deposits is excess reserve ratio which is non-compulsory.

金融机构超额准备金账户占其存款总额的比例叫做超额储备金率，它是非强制性的。

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"We prefer voluntary readmission, but we also agree that we must reserve the right to compulsory repatriation, " Danish Immigration Minister Bertel Haarder, whose country holds the EU presidency, said.

BBC: EU backs action on illegal migrants