combinatorial group theory

例句：

1. 1.This research is crucial for understanding the combinatorial properties of graphs.
   这项研究对于理解图的组合性质至关重要。
2. 2. The combinatorial group theory has been applied to various fields, such as computer science and mathematics.
   组合群论已被应用于计算机科学和数学的各个领域。
3. 3. In combinatorial group theory, we study how to efficiently generate all possible subsets of a given set.
   在组合群论中，我们研究如何高效地生成给定集合的所有可能子集。