She found an envelope in the jar with the message: "I hope this money will help you and your family in these rough times."

VOA: special.2010.02.05

You're familiar with this, if I had a jar of acetone or some kind of a volatile liquid, let's say I have perfume.

举个常见的例子,假如你有一瓶丙酮或者其它挥发性液体,就说香水吧

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