PEC

例句：

1. 1. PEC stands for Personal Electronic Check-In, which is a system used at airports to check in passengers electronically.
   PEC代表个人电子登机，是机场用于乘客电子登机的系统。
2. 2. The PEC team was responsible for developing the new software.
   PEC团队负责开发新软件。
3. 3. During the PEC meeting, they discussed the project's progress and future plans.
   在PEC会议上，他们讨论了项目的进展和未来计划。