"炮灰"means the cannon fodder. Now, it indicates someone who is sacrificed for other's benefits.
例句 Sentences
1、在这场交易里,他就是一个炮灰。 Zài zhè chǎng jiāoyì lǐ, tā jiùshì yí ge pàohuī. He was the victim in the exchange.
2、他在办公室天天扮演炮灰的角色,老挨领导的批评。 Tā zài bàngōngshì tiāntiān bànyǎn pàohuī de juésè, lǎo ái lǐngdǎo de pīpíng. He was the victim in the office who was always criticized by his boss.