The teacher told the children to stop clacking their pencils.老师叫孩子们别哒哒地敲铅笔。The toy is made so that when you hold the top square, the rest fall down one after another, making a clacking noise.这种玩具，你拿着最上面的方块，其余的就会哗啦啦地一块接一块落下来。I heard her heels clacking down the hall.我听见她走过大厅时鞋跟咔咔响。