赤ㄔˋ膊ㄅㄛˊ上ㄕㄤˋ陣ㄓㄣˋchìbó‑shàngzhèn

简赤膊上阵

光著膀子上陣打仗。形容恃勇輕敵，猛打猛衝；也比喻不加掩飾地做某事（多含貶義）。例「看樣子這夥匪徒要赤膊上陣，跟警方死拼了」。

英lit. to go into battle bare-breasted (idiom), fig. to go all out, to come out in the open