weak at the knees
腿軟
口語·描述強烈情感
英文釋義
physically or emotionally affected by something in a powerful or overwhelming way
例句
When he saw her walk in, he felt weak at the knees.
典故來源
源自生理反應,因強烈情感(如愛慕、恐懼)導致膝蓋無力,形容激動或緊張。