5 sentences

1. 隔夜的饭菜容易变质。

   gé​yè de fàn​cài róng​yì biàn​zhì.

   Overnight leftovers spoil easily.

   Source: Dong Chinese Dictionary

2. 我吃了点变质的鱼。

   wǒ chī le diǎn biàn​zhì de yú.

   I ate some bad fish.

   Source: OpenSubtitles

3. 由于天气炎热，剩菜已经变质了。

   yóu​yú tiān​qì yán​rè, shèng​cài yǐ​jīng biàn​zhì le.

   The leftovers have gone bad because of the heat.

   Source: Dong Chinese Dictionary

4. 要警惕腐朽思想使人变质。

   yào jǐng​tì fǔ​xiǔ sī​xiǎng shǐ rén biàn​zhì.

   We must be wary of decadent ideas causing moral degradation.

   Source: Dong Chinese Dictionary

5. 变质作用形成了许多独特的矿石。

   biàn​zhì zuò​yòng xíng​chéng le xǔ​duō dú​tè de kuàng​shí.

   Metamorphism has formed many unique minerals.

   Source: Dong Chinese Dictionary