2 sentences

1. 前线部队急需后援。

   qián​xiàn bù​duì jí xū hòu​yuán.

   Frontline troops are in urgent need of reinforcements.

   Source: Dong Chinese Dictionary

2. 粉丝们成立了后援会来支持这位歌手。

   fěn​sī men chéng​lì le hòu​yuán huì lái zhī​chí zhè wèi gē​shǒu.

   Fans formed a fan club to support the singer.

   Source: Dong Chinese Dictionary