nián / qīng / shí / zhǐ / zhēng / zhāo / xī / lǎo / le / cái / bú / huì / wèi / xū / dù / guāng / yīn / ér / hòu / huǐ

年轻时只争朝夕，老了才不会为虚度光阴而后悔。

If we make the most of our time when we are young, we will not regret wasting it when we grow old.