jīng / lì / le / xǔ / duō / biàn / gù / hòu / ， / tā / zhōng / yú / xīn / rú / zhǐ / shuǐ / ， / bú / zài / wéi / xiǎo / shì / fán / nǎo / 。

经历了许多变故后，他终于心如止水，不再为小事烦恼。

After experiencing many changes, he finally became peaceful and was no longer troubled by small things.