【例句】Stop laughing so loudly—people will think you're as nutty as a fruitcake.【误解】不要这么大声谈笑——别人会认为你们像水果蛋糕一样硬。

【正确】不要这么大声谈笑——别人会认为你们有精神病。

【说明】fruitcake是“水果蛋糕”。

as nutty as a fruitcake是个固定短语，相当于completely insane, very eccentric(非常疯癫的，行为古怪的)。