3 sentences

1. 我们不必自相残杀。

   wǒ​men bù​bì zì​xiāng​cán​shā.

   We don't have to kill each other.

   Source: OpenSubtitles

2. 我们不能自相残杀。

   wǒ​men bù néng zì​xiāng​cán​shā.

   We can't kill each other.

   Source: OpenSubtitles

3. 内部的自相残杀只会让敌人有机可乘。

   nèi​bù de zì​xiāng​cán​shā zhǐ huì ràng dí​rén yǒu​jī​kě​chéng.

   Internal infighting will only give the enemy an opportunity to exploit.

   Source: Dong Chinese Dictionary