If + present simple, + present simple.
- If you freeze water, it turns into ice.
- If I work too much, I get tired.
- If I have time, I usually go to the movies.
- If she eats hamburgers, she gets an allergy.
- If they come here, they always bring a present.
If + present simple, + will + infinitive.
- You’ll miss the train if you don’t hurry!
- If I miss the train today, I’ll drive to work.
- I will pass my math exam if I study hard.
- If it rains, we won’t have our picnic.
- If you stay out in the rain too long, you’ll get sick!
If + past simple + would + infinitive.
- If I won the lottery, I would buy a big house.(I probably won't win the lottery)
- If I met the Queen of England, I would say hello.
- She would travel all over the world if she were rich.
- She would pass the exam if she ever studied.(She never studies, so this won't happen)
- If I were you, I would drive more carefully in the rain.
If + past perfect, + would + have, + past participle.
- If I had gone to university, I would have studied medicine.
- If You had gone to the party, you would have met him.
- We wouldn’t have driven all this way if we had known the museum was closed.
- If I had known that you needed a ride to school, I would have driven you.
- I really wanted to see that movie! If I had known you were going, I would have gone with you!