weak in the knees
雙腿無力的；因為緊張或興奮而感到腿軟的
口語·表達震驚或緊張
英文釋義
to feel a sudden loss of strength or confidence, often due to strong emotions or attraction
例句
The news of the accident made her weak in the knees.
典故來源
與“weak at the knees”同源，強調(diào)因情緒沖擊而失去支撐力。