![](https://cos-cdn.shuashuati.com/pipixue-wap/2020-1230-1107-56/ti_inject-812ce.png)
There was another student standing in front of the shelf. I stood next to him and started to look for my book. Then he looked very upset and said, “Excuse me!” and moved away. I didn’t know what was wrong. I was confused. I learned later that you shouldn’t stand very close to other people in the U.S. ( )