knee jerk reaction
膝反射反应，指没有经过深思熟虑的即时反应或反应。
口语·描述本能反应
英文释义
an immediate and automatic response, often without careful thought or consideration
例句
His knee jerk reaction was to say no, but he later reconsidered.
典故来源
源自医学膝跳反射，指自动反应，引申为未经思考的冲动回应。