series classification

例句：

1. 1.In the series classification, each item is assigned a unique number.
   在系列分类中，每个项目都有一个唯一的编号。
2. 2.The series classification helps us understand the relationship between different elements in the system.
   系列分类有助于我们理解系统中不同元素之间的关系。
3. 3. The series classification is crucial for organizing and analyzing data effectively.
   系列分类对于有效地组织和分析数据至关重要。