There are four types of conditional sentences in English.
We use Zero Conditional to talk about actions and situations or conditions that always lead to the same results or consequences.
The form is:
If + Present Simple, .... Present Simple.
If water reaches 100 degrees, it boils.
If I eat peanuts, I get allergy.
First Conditional is used to talk about possible future events or consequences which depend on other future events or conditions.
The form is:
If + Present Simple, .... Future Simple.
If she gets good marks today, they will go to the park.
If you are late, we will go without you.
The form of the Second Conditional is:
We use Second Conditional:
if we talk about impossible situations in the present:
If they did their homework, they would get a lot of sweets.
If I had more time, I would not eat fast food.
if we talk about imagined, unlikely or impossible events in the future:
If I had three children, I would play with them all the time.
If I won a lot of money, I would buy a new car.
We use Third Conditional to talk about unreal situations in the past, to imagine things that did not happen:
The form is:
The mixed condition is formed:
The mixed condition is used to talk about:
imaginary past events that could have some consequences in the present:
If he had broken the record, he would be famous now.
unreal present situations, usually imaginary states, which could have had some consequences in the past:
If she did not speak few languages, she would not have got that job.