Long-period comets,however, may take several hundred years to orbit the sun.

VOA: special.2011.02.09

Stocks have paid 4% more a year over this incredibly long time period than short-term bonds.

股票在相当长的一段时间里,每年都比短期债券投资收益率,高出4个百分点。

耶鲁公开课 - 金融市场课程节选

That's where I--once that gets going, it goes for a long period of time.

一旦开始了,就喋喋不休

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