ph.
1. The small ball dropped back to the floor.
小球又落回到地板上。
2. The car dropped back halfway through the race.
那辆车跑了一半赛程就落后了。
1. 退后：sizeable enterprise 大型企业 | drop back 退后 | viminal [植](发)小枝的
2. 坠后：132.后撤:back off | 133.坠后:drop back | 134.收缩;回收:jamming
3. 退后, 后撤 恢复(旧习惯等)：drop away (一个一个地)离开, 散去 | drop back 退后, 后撤 恢复(旧习惯等)(into) | drop behind 落 伍, 落后, 落在...之后
4. 回防：Dribble-盘扭. | Drop Back-回防. | Formation-阵式.
verb
1. take position in the rear, as in a military formation or in the line of scrimmage in football
e.g. The defender dropped back behind his teammate
2. to lag or linger behind
e.g. But in so many other areas we still are dragging