介绍:
drop in顺便拜访;顺便进入 drop in on somebody顺便拜访某人 drop in at someplace顺便拜访某地 The Wilsons  dropped in on us just as we finished dinner. 威尔森一家在我们刚吃完晚饭时就突然拜访。 Please drop in on us when you happen to be free. 如果你碰巧有空,请到我的办公室来。
上一期: keep one's head
下一期: out of breath