wolf in sheep's clothing从字面理解其意思，就是“披着羊皮的狼”，所以它可以进一步引申为“伪君子，实际和表面正相反的人”。

【例句】
Do not trust him, he is totally a wolf in sheep's clothing.
别相信他，他是个彻头彻尾的伪君子。

He is a wolf in sheep's clothing, outwardly kind but inwardly vicious!
他是个披着羊皮的狼，外貌仁慈，内心狠毒！