日久

mù tou de yán sè suí zhe rì jiǔ ér biàn shēn

木头的颜色随着日久而变深。

The color of the wood darkens with the passing of time.

rì jiǔ tiān cháng shí jiē yǐ jīng mó de guāng liū liū de

日久天长，石阶已经磨得光溜溜的。

As time goes by, the stone steps had worn smooth.