Inflation was so high that the notes were like Monopoly money.

通货膨胀严重，货币变得跟“大富翁”游戏钞票无异。

《牛津词典》

Accomplishments are the Monopoly money of life.

成就是生活金钱化的主宰。

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In the romantically primed group, the men went wild with the Monopoly money.

在充满浪漫气氛的第一组成员中，男人们疯狂地想完全占有金钱。

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All too often, however, they actually treat foreign banknotes as though they were Monopoly money.

ECONOMIST: The value of a coin or banknote depends on its familiarity

Or could his signature mean something else in Chinese, like "We will bury you" or "This is Monopoly money"?

CNN: Jack Lew: The signature that goes 'boing'!

And at Wal-Mart Stores and Starbucks, it's as useful as Monopoly money.

FORBES: Magazine Article