Conditional sentences

This is just a basic introduction to conditionals. We'll cover it in more detail later in Grammar Basics.

Type 1:

• present tense: if-clause verb
• main clause verb: future simple
• Meaning: Probable – present or future

Examples:

If it rains, we will stay home.
If it gets dark, we’ll turn on the lights.

Variations:

• (if + present) + may/might
• Meaning: Possibility

• Examples:
• If it snows too much, we might have to stay home from school.
• If he eats too much, he may get a stomachache.
  

• (if + present) + may/can
• Meaning: Permission; possibility
• Examples:
• If you finish your homework, you may go outside and play.
• If he cleans his room, he can take a break.

• (if + present) + must, should, etc.
• Meaning: Request or advice
• Examples:
• If you catch a cold, you should stay in bed and drink plenty of fluids.
• If it snows, you must shovel the sidewalk.

• (if + present) + another present tense
• Meaning: Automatic or habitual results
• Examples:
• If the power goes out, the emergency backup lights come on.
• If he gets a haircut, he tips 20%.

• if + present continuous
• Meaning: Present action or future arrangement
• Examples:
• If I eat one more piece of candy, I’m going to feel sick.
• If Father comes home early, we will go to the park.

Type 2:

• if-clause verb: past tense
• main clause verb: conditional tense (would)
• Meaning: Subjunctive (certain result)

Examples:

If the baby fell, he would cry.
If I wrote a book, I would be famous.

Variations:

• (if + past) + might/could
• Meaning: Possible result; ability or permission
• Examples:
• If it rained, the game might have been cancelled.
• If the train was late, you could have taken the bus.

• (if + past) + past tense
• Meaning: Automatic or habitual reactions in the past
• Examples:
• If the baby cried, Mother would always pick him up.
• If he got mail, Grandfather would sit on the porch and read it.

Type 3:

• if-clause verb: past perfect tense
• main clause verb: perfect conditional (would have)
• Meaning: Unfulfilled

Examples:

If I had known you were coming, I would have baked you a cake.
If I had gotten up early, I would have avoided the morning rush.

Variations:

• (if + past perfect) + might/could have
• Meaning: Possibility; ability, permission
• Examples:
• If he had gotten good grades, he could have been accepted to his first-choice university.
• If they had taken a trip to New York, they might have been on that plane that crashed.

• (if + past perfect) + would have been –ing (continuous form of perfect conditional)
• Examples:
• If the police had caught him, he would have been wearing a prison uniform by now.
• If he had been tired, he would have sleeping.

• (if + past perfect continuous) + would have been –ed
• Examples:
• If it had been raining, the car would have been parked in the garage.
• If he had been outside raking leaves all day, he would have been tired.