例句：

　　He walked back and forth in the room, thinking about the problem.

　　他在屋里来回走动，思考着问题。

　　Don't say this back and forth, I know how to do.

　　不要反复说这个，我知道该怎么做。

　　A:Please don't go back and forth, I'm doing my homework.

　　请不要来回走动，我在写作业。

　　B:Oh, I'm sorry, I didn't notice that you were doing your homework.

　　哦，对不起，我没注意到你在写作业。

　　背景音乐：

　　Before You Break My Heart — Stevie Hoang