This document discusses the different types of conditionals in English. It explains that conditionals are used to speculate about possible, unlikely, or unreal situations. It defines four types of conditionals: 1) Zero conditional refers to general facts using the present tense. 2) First conditional refers to possible future conditions using the present and future tenses. 3) Second conditional expresses improbable conditions using past tense. 4) Third conditional expresses unreal past conditions using past perfect and conditional tenses. Examples are provided for each type.