一.Mechanisms of E1, E2, and E1cB 二.E2 Reaction 三.E1 Reactipn 四.Competition of E2/E1, E/S 五.E1cB Reaction 一.Mechanisms of E1, E2, and E1cB 二.E2 Reaction 三.E1 Reactipn 四.Competition of E2/E1, E/S 五.E1cB Reaction 六.Other Elimination Reactions Reactivity Regeoselectivity Stereochemistry