2 sentences

1. 他把发黄的衣服洗白了。

   tā bǎ fā​huáng de yī​fu xǐ bái le.

   He washed his yellowed clothes until they were white.

   Source: Dong Chinese Dictionary

2. 这件白衬衫穿久了发黄，需要用漂白剂漂白一下。

   zhè jiàn bái chèn shān chuān jiǔ le fā​huáng, xū​yào yòng piǎo​bái​jì piǎo​bái yī​xià.

   This white shirt has yellowed over time and needs to be whitened with bleach.

   Source: Dong Chinese Dictionary