Metaphor has been studied for over two thousand years. Traditionally it was only treated as a kind of linguistic ornament, the frosting on the cake merely, sweet tasting but not necessary.

隐喻研究有两干多年的历史，传统隐喻仅仅把它看成语言的装饰，如同蛋糕上的糖衣，美味可口，但不是必需的。

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The smeared colours looked glorious, like rich, thick frosting on a cake.

涂抹的颜色看起来绚丽多彩，就像蛋糕上厚厚的糖霜。

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If you "ice" a cake, you're putting frosting (" icing ") on the cake.

如果你说ice a cake，就表示你在蛋糕上加了霜状白糖。

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"Another four years would have been frosting on the cake, but we have a nice cake now, " said William Borucki, the project's principal scientist.

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The frosting on this scrumptious digital cake is that I can even make phone calls although texting is usually faster.

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