You have a freewill offering--just because someone wants to do this, a freewill offering. And you have a vow offering that would be offered on the successful completion of a vow, for example. And these sacrifices are all entirely optional.

自由祭品--只因为有人想这么干，自由祭品，还有一个誓言祭品,举个例子，一个誓言如果成功达成，便会供奉祭品，这些祭品都是可选择的。

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Zandt offered the example of the American Society for the Prevention of Cruelty to Animals.

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When pressed, Stephen Tetlow, chief executive of IMechE, offered the example of coal-fired power stations.

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Dickens offered the example of Fezziwig, under whom Scrooge apprenticed and apparently learned only selectively.

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