fixed type bar

例句：

1. 1. The barcode on the package is for tracking purposes only.
   包装上的条形码仅用于追踪目的。
2. 2. The serial number on the license plate helps to identify the vehicle.
   车牌上的序列号有助于识别车辆。
3. 3.The barcode scanner is used to read and store information in a database.
   条形码扫描器用于读取和存储信息到数据库中。