“挺身而出”，汉语成语，形容面对着艰难或危险的事情，勇敢地站出来。可以翻译为“step forward bravely (boldly)，come out boldly”等。

例句：

警方呼吁证人挺身而出。

Police have appealed for witnesses to come forward.

他挺身而出，对这种谬论加以反驳。

He stepped forward bravely and refuted the lies.