exchange pair ing

例句：

1. 1. They exchanged information about the new project.
   他们交换了关于新项目的情报。
2. 2. The two countries have been exchanging diplomats for years.
   这两个国家多年来一直在互派外交官。
3. 3.He exchanged pleasantries with his colleague before leaving.
   他离开前与同事寒暄了几句。