There are four main types of English conditionals: zero, first, second, and third.
Zero Conditional
The zero conditional describes a general truth or a fact. It uses the present simple in both clauses:
- If + present simple, present simple
Examples:
- If you heat water to 100 degrees Celsius, it boils.
- If you drop a ball, it falls to the ground.
First Conditional
The first conditional describes a possible future situation and its likely consequence. It uses the present simple in the if clause and the will/won't + base form of the verb in the main clause:
- If + present simple, will/won't + base form
Examples:
- If you study hard, you will pass the exam.
- If it rains, we won't go to the park.
Second Conditional
The second conditional describes an unlikely or hypothetical situation and its result. It uses the past simple in the if clause and would/wouldn't + base form of the verb in the main clause:
- If + past simple, would/wouldn't + base form
Examples:
- If I won the lottery, I would travel the world.
- If you were a bird, you would fly away.
Third Conditional
The third conditional describes a past situation that did not happen and its imagined result. It uses the past perfect in the if clause and would have/wouldn't have + past participle in the main clause:
- If + past perfect, would have/wouldn't have + past participle
Examples:
- If you had studied harder, you would have passed the exam.
- If I had known you were coming, I would have cooked dinner.
Mixed Conditional
While not considered a separate conditional, a mixed conditional combines the second and third conditionals to describe a hypothetical situation in the past that has a present consequence.
- If + past perfect, would/wouldn't + base form
Examples:
- If you had studied harder, you would be passing the exam now.
- If I had known you were coming, I would be cooking dinner right now.
