- 刀不磨要生锈，人不学要落后 dāobùmóyàoshēngxiùrénbùxuéyàoluòhòu knowledge is like a bladeA blade will get rusty if it is not sharpened; a man will fall behind if he doesn't study.
- 永不生锈的螺丝钉 yǒngbùshēngxiùdeluósīdīng a screw that never rustsA metaphor used to praise loyal and selfless contributors who work hard for the common good, famously applied to the model worker [[雷锋|雷鋒|lei2 feng1]].
