Conditional sentences

We use conditional sentences to say one thing depends on another. They can be used to talk about real or imaginary situations. One of the clauses starts with if (or a similar word) – this is the conditional clause. The other clause talks about the result of the conditional clause happening.

1. This kind of conditional sentence (Type 1) is used to talk about a possible present or future situation and its result.
2. You can use any present tense in the if clause and any form of the future in the other clause.

2. Type 2 conditional sentences are used to talk about hypothetical or improbable situations in the present or future.
3. You can use the past tense (simple or continuous) in the if clause and would + infinitive (or could / might) in the other clause.

3. Type 3 conditional sentences are used to talk about a hypothetical situation in the past.
4. You can use the past perfect (simple or continuous) in the if clause and would have + infinitive (or could / might have) in the other clause.

If we want to refer to the present and the past in the same sentence, we can mix tenses from two different types of conditionals, e.g. I wouldn’t be in this mess (type 2) … if I had listened to your advice (type 3). Jane would have left Mike by now (type 3) … if she didn’t still love him (type 2).