zero conditional(type 0)
If you heat ice, it melts.
If+present simple, present simple
first conditional(type 1)
If it rains, I will stay at home.
You’ll get good marks if you revise well.
If+present simple, will/won’t+verb(infinitive)
second conditional(type 2)
If I won the lottery, I would buy a car.
If I were you, I would apologise.
If+past simple, would/wouldn’t+verb(inf)
third conditional(type 3)
If I had won the lottery, I would have bought a car.
If+past perfect, would have+past participle