a snake in the grass

【字面理解】草丛中的蛇

【英文解析】a pCTson who pretends to be your friend but cannot be trusted

【中文解析】 (伪善地装成朋友的)阴险之人;潜伏的敌人; 隐患

【例句】① We used tQ be fiiends, but who knew he would turn out to be such a snake in the grass?我们曾经是好朋 友，可谁知道他会是一个阴险的人。

② Beware of him. He appears to be friendly iand helpful but is a real snake in the grass.小心提防着他D他看起来好像 很友好，又肯帮助人，但其实却是个阴险的家伙。

【注释】最早出自维吉尔(Virgil)的《牧歌》(Eclogues)： a cold snake lurks in the grass.(蛇隐藏于青草之中。) 现在喻指“隐患;暗藏的敌人;背后捣鬼的人”等。