3 sentences

1. 他在足球比赛中担任前卫。

   tā zài zú​qiú bǐ​sài zhōng dān​rèn qián​wèi.

   He plays as a midfielder in football matches.

   Source: Dong Chinese Dictionary

2. 这位艺术家的作品风格非常前卫。

   zhè wèi yì​shù​jiā de zuò​pǐn fēng​gé fēi​cháng qián​wèi.

   This artist's style of work is very avant-garde.

   Source: Dong Chinese Dictionary

3. 部队的前卫已经抵达了预定位置。

   bù​duì de qián​wèi yǐ​jīng dǐ​dá le yù​dìng wèi​zhi.

   The vanguard of the troops has reached the designated position.

   Source: Dong Chinese Dictionary