半: half群: crowd; group论坛: forum; tribune群论: group theory; grouping theory; theory of groups半群: demigroup; hemigroup; semi group; semigroup阶（群论）: order李群论: theory of lie groups群论的: grouptheoretical中心 (群论): center (group theory)半群法: semigroup method半群性: semigroup property半群组: semi group纯半群: pure semigroup单半群: simple semigroup零半群: zero semigroup么半群: monoid商半群: quotient semigroup子半群: subsemigroup幺半群: monoid数学群论: mathematical group theory有限群论: theory of finite groups组合群论: combinatorial group theory论坛: forum; tribune 文艺论坛 forum on literature物理中的群论: groutheory in physics半群代数: semigroualgebra
