n.短促的敲打（聲）; 爆震聲; 敲擊聲; 敲門（或窗等）聲;
vi.猛烈敲擊; 與某物相撞; 撞到了桌子;
vt.（心）怦怦跳; 把…撞擊成（某種狀態）; 批評;
第三人稱單數：knocks過去分詞：knocked復數：knocks現在進行時：knocking過去式：knocked
例句:
1.
My first night there, I was curled up with a glass of wine and a good book when I heard a knock on the door.
搬去那裏的第壹個晚上，我拿著壹杯葡萄酒和壹本好書蜷坐在屋裏，這時我聽到了敲門聲。