TYPE 1,2,3
TYPE 1 If clause Habit e.g. If / When I have money, Present simple Main clause I usually buy a lottery ticket. Present simple
TYPE 1 If clause advice e.g. If you have money, Present simple Main clause buy a lottery ticket! Imperative
TYPE 1 If clause real condition e.g. If I have money, Present simple Main clause I will buy a lottery ticket. Future simple
TYPE 2 If clause Possible / imaginary condition e.g. If I had money, If I were you, Were I you, Past simple Main clause I would buy a ticket. I’d buy a ticket. Would + verb
TYPE 3 If clause impossible condition e.g. If I had had money, Past perfect Main clause I would have bought a ticket. Would+ have+ vb3
If unless providing (that) suppose/ supposing (that) when