If you rest, you rust.

如果你休息，你就要生锈。

youdao

And thus, the saying goes, "If you rest, you rust."

所以有一种说法：“如果你休息了，你就生锈了”。

youdao

Skills decline, rust if you like, when not in use.

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On the eve of his departure, Isaac gets together with his best friend Billy Poe, a former high-school football star who has also failed to heed the edict that at 18 you should flee the rust belt altogether.

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