Conditionals

ZERO CONDITIONAL

IF + PRESENT SIMPLE, PRESENT SIMPLE

If you heat water, it boils.
I feel tired if I don’t get enough sleep.
If you see an accident, call an ambulance.
- Use: for facts that are generally true. This means that one thing follows immediately from another.
- We can use an imperative form in the second clause.


FIRST CONDITIONAL

IF + PRESENT SIMPLE, WILL + INFINITIVE

If we don’t hurry, we won’t catch the bus.
She’ll be angry if I’m late.
If we are expecting visitors, I’ll do the shopping.
If you go jogging regularly, you may lose weight.

- Use: to talk about things that may happen in the future.
- We can use the present continuous or the present perfect in the ‘if clause’.
- We can use other modal verbs instead of ‘will’ (e.g. can, might, should…)


SECOND CONDITIONAL

IF + PAST SIMPLE, WOULD + INFINITIVE

If Rachel got up earlier, she wouldn’t be late.
I’d buy a new car if I were you.
If she were playing the piano, it would be noisier.
If we had a calculator, we could do it quicker.

- Use: to talk about a hypothetical or imaginary situation.
- We sometimes use ‘were’ instead of ‘was’, especially in the clause ‘if I were you’ (for advice).
- We can use the past continuous in the ‘if clause’.
- We can use ‘could’ or ‘might’ instead of ‘would’.


THIRD CONDITIONAL

IF + PAST PERFECT, WOULD + PRESENT PERFECT
If you had phoned her, she wouldn’t have been so annoyed.
I’d have passed my test if I hadn’t made that mistake.
If I’d had my mobile, I could have contacted you.

- Use: to talk about things in the past happening differently from the way they really happened. This sometimes means criticising people or pointing out their mistakes.
- We can use ‘could’ or ‘might’ instead of ‘would’.

NOTE: instead of ‘if’ (mainly in the first conditional), we can use other particles:
- Unless (‘if… not’): I won’t go to the party unless she invites me.
- Provided / providing / as long as (only if): I’ll go home providing you don’t want me to stay.
- In case: I’ll buy some food in case Tom comes.

1. Future time clauses
We use the present simple after ‘when, as soon as, until, before and after’ to talk about the future.
I’ll call you as soon as I arrive.
We’ll have dinner when your grandparents get home.
After I finish university, I’ll probably take a year off to travel.
I’ll call you before I leave.
I won’t go to bed until you come home.

2. Mixed conditional
We can mix the second and the third conditionals.

a) IF + PAST SIMPLE, WOULD + PRESENT PERFECT
If Tom was more sensible, he would have worn a suit to the interview.
If I didn’t have all this work to do, I would have gone out for the day.

b) IF + PAST PERFECT, WOULD + INFINITIVE
If you had planned things at the start, we wouldn’t be in this mess now.
If you hadn’t left all these dirty dishes, the place would look a bit tidier.