下的零元。则：
交换律.设formula_11: formula_12是集合formula_1上的二元运算，则：称formula_11满足交换律，若formula_11满足：formula_117；
结合律.设formula_11: formula_12是集合formula_1上的二元运算，则：称formula_11满足结合律，若formula_11满足：formula_123；
消去律.设formula_11: formul