Conditionals

We use conditional sentences (if clauses) to say what the result will be if a certain condition is met.

If the weather is good, we will go to the park.

In this sentence, the condition is the weather. The result of good weather is that we will go to the park. We will only go to the park if the weather is good. If it rains we will stay home.

All conditional sentences have 2 parts: the conditional clause that starts with if, and the main clause that tells us the result.

If I win the lottery, I will buy a car.

conditional clause= If I win the lottery

main clause= I will buy a car

It doesn't matter which part you put first, the sentence has the same meaning.

I will buy a car if I win the lottery.

main clause= I will buy a car

conditional clause= if I win the lottery

There are 4 types of conditionals:

  1. Zero conditional;
  2. 1st conditional;
  3. 2nd conditional;
  4. 3rd conditional.

We use the different types to show how possible or likely the result is.

Zero Conditional

We use the zero conditional when the result is guaranteed. The result always happens when the condition is met.

The zero conditional is commonly used for facts and things that are always true.

If you heat water to 100 degrees, it boils.

Water always boils when you heat it to 100 degrees. It is guaranteed that the water will boil.

Making Zero Conditional Sentences

In the zero conditional, the conditional clause and the main clause are both in the present tense.

+ If you heat water to 100 degrees, it boils. If + s='you' + v ... + s='it' + v

- If you don't heat water to 100 degrees, it doesn't boil. If + s='you' + do not + v ... + s='it' + does not + v

? If you heat water to 100 degrees, does it boil? If + s='you' + v ... + does + s='it' + v

1st Conditional

We use the 1st conditional when the result is possible or likely.

If I win the lottery, I will buy a car.

It is possible that you will win the lottery because you have bought a ticket. If you win, you will use the money to buy a new car.

If it rains, we will have the party inside.

You are having a party. It is possible it will rain. If it does rain, the party will be inside.

Making 1st Conditional Sentences

In the 1st conditional, the conditional clause is in the present tense and the main clause uses 'will' and a verb.

+ If I win the lottery, I will buy a car. If + s='I' + v ... + s='I' + will + v

- If I don't win the lottery, I will buy a car. If + s='I' + do not + v ... + s='I' + will + v

- If I win the lottery, I won't buy a car. If + s='I' + v ... + s='I' + will + not + v

? If you win the lottery, will you buy a car? If + s='you' + v ... + will + s='you' + v

2nd Conditional

We use the 2nd conditional when the result is unlikely or impossible. We use it to talk about imaginary situations.

If I won the lottery, I would buy a car.

It is impossible to win the lottery, because you haven't bought a ticket. You are imagining what you would do if you had bought a ticket and you won.

If it rained at my party, I would cry.

You are imagining you are having a party. You would cry if it rained.

You can use other modals instead of 'would' in the main clause. For example, you can 'might' if you are not certain of the result, or you can use 'could' to say the result is something you are able to do.

Learn more about using might and could.

Making 2nd Conditional Sentences

In the 2nd conditional, the conditional clause is in the past simple tense and the main clause uses 'would' and a verb.

+ If I won the lottery, I would buy a car. If + s='I' + past v='won'... + s='I' + would + v

- If I didn't win the lottery, I would buy a car. If + s='I' + did not + v ... + s='I' + would + v

- If I won the lottery, I wouldn't buy a car. If + s='I' + past v='won' ... + s='I' + would + not + v

? If you won the lottery, would you buy a car? If + s='you' + past v='won' ... + would + s='you' + v

Learn more about past simple verbs.

3rd Conditional

We use the 3rd conditional to talk about the past. It refers to something that was possible in the past, but didn't happen.

If I had won the lottery, I would have bought a car.

You bought a ticket last week. The lottery has finished, and you didn't win. If you had won, you would have used the money to buy a car. You didn't win and you didn't buy a car.

If it had rained, we would have had the party inside.

You had a party. You thought it might rain, but it didn't. You planned to have the party inside if there was rain.

Making 3rd Conditional Sentences

In the 3rd conditional, the conditional clause is in the past perfect tense and the main clause uses 'would have' and a past participle.

+ If I had won the lottery, I would have bought a car. If + s='I' + had + past participle='won'... + s='I' + would have + past participle='bought'

- If I hadn't won the lottery, I would have bought a car. If + s='I' + had not + past participle='won' ... + s='I' + would have + past participle='bought'

- If I had won the lottery, I wouldn't have bought a car. If + s='I' + had + past participle='won' ... + s='I' + would + not + have + past participle='bought'

? If you had won the lottery, would you have bought a car? If + s='you' + had + past participle='won' ... + would + s='you' + have + past participle='bought'

Learn more about past participles and the past perfect.