It should immediately announce that in the event of a Greek exit from the eurozone it will stand ready to buy unlimited amounts of the sovereign bonds of countries remaining in the euro for a limited period of time – say a year or 18 months. 欧洲央行应该马上宣布,如果希腊退出欧元区,它将随时准备在一段有限的时间里(如1年或者18个月)无限额地购买欧元区其余国家的主权债券。