Federal Reserve officials announced a plan to purchase up to $300 billion in long-term U.S.government bonds to bolster the nation's economy.

VOA: standard.2009.03.18

These are long-term government bonds and I--now these are--since they're long-term, they have some uncertainty and variability to them.

这些是长期政府债券,由于它们是长期的，就存在不确定性和变化性。

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