2 sentences

1. 他身陷绝地，只能背水一战。

   tā shēn xiàn jué​dì, zhǐ néng bèi​shuǐ​yī​zhàn.

   Trapped in a desperate situation, his only option was to fight a last-ditch battle.

   Source: Dong Chinese Dictionary

2. 面对敌人的威胁，他别无选择，只能背水一战。

   miàn​duì dí​rén de wēi​xié, tā bié​wú​xuǎn​zé, zhǐ néng bèi​shuǐ​yī​zhàn.

   Faced with the enemy's threat, he had no choice but to fight a last-ditch battle.

   Source: Dong Chinese Dictionary