secondary classification

例句：

1. 1. In the study of economics, secondary classification is crucial for understandingmarket dynamics.
   在经济学研究中，次级分类对于理解市场动态至关重要。
2. 2. The team decided toclassify the data into two maincategories: quantitative and qualitative.
   该团队决定将数据分为两个主要类别：定量和定性。
3. 3. The researcher used secondary classification techniquesto analyze the data more effectively.
   研究者使用次级分类技术更有效地分析了数据。