Conditionals

Form

condition clause*, result clause
result clause + condition clause

*Condition clauses are sometimes called if-clauses. However, conditional sentences can be made without if (See conditional sentences without if.)

There are different types of conditionals

Conditionals are sometimes classified as zero, first, second and third conditionals

First conditional
If they offer me the job, I'll take it.
Future condition, future result.
Second conditional
If they offered me the job, I would take it.
Imaginary or unreal condition (present or future), imaginary or unreal result (present or future).
Third conditional
If they had offered me the job, I would have taken it.
Unreal condition in the past, unreal result in the past.
Zero conditional
If I go for an interview, I always do some research on the company first.
Generally true condition, generally true result.
If we worked weekends, we were paid a bonus.
Generally true condition in the past, generally true result in the past.

Another way is to distinguish between normal and special use of tenses

Michael Swan, Practical English Usage (OUP), suggests classifying conditional sentences into two main kinds:

Conditionals with ordinary (normal) use of tenses
If I have time later, I will call you.

Conditionals with special use of tenses
If we had more time, we could go to the museum.

Real situations use normal tenses; unreal situations use special tenses

Real situations with normal use of tenses

If I have time later, I will call you.

This sentence is about a real situation in the future. It is real because it is possible that I will have time. Normal tenses are used. The present simple is used after if because present tenses are normally used for future events after time conjunctions such as if, when and until. A will future is used as this is a spontaneous decision.

Unreal situations with special use of tenses

If we had more time, we could go to the museum.

This sentence is about an unreal situation now. The reality is that we do not have more time so we can't go to the museum. The past tense is used after if, and could is used in the result clause. This is a special use of the past tense as the sentence is not about the past - the past tense is used to show an unreal or imaginary situation.

Mixed conditionals

Some conditional sentences do not follow the time relationships shown above. See mixed conditionals for more details.

Examples of common conditional sentences

The table shows examples of some common types of conditionals. It does not include all possible variations - especially with real conditionals, where various combinations of verb forms are possible. Follow the links on the right for more details of the various types.

Example

Time

Real / imaginary

Tenses

Name

If I eat prawns, I get a rash.

generally true

real

normal

zero conditional

If I see Peter, I'll tell him about the party.

future

real

normal

first conditional

If I get time tomorrow, I'm going to wash the car.

future

real

normal

first conditional

If you're going to the shop, can you get some eggs?

future

real

normal

first conditional

If you've finished your homework, you can watch TV.

future

real

normal

first conditional

If they left at one o'clock, they'll be here by three.

past / future

real

normal

mixed conditional

If we were late, the teacher got angry.

generally true (past)

real

normal

zero conditional

If I had time, I'd travel more.

now / future

unreal

special

second conditional

If I were younger, I'd study computing.

now / future

unreal

special

second conditional

If we had some money, we could get a taxi.

now / future

unreal

special

second conditional

If we had some money, we could get a taxi.

now / future

unreal

special

second conditional

If I found some money in the street, I'd keep it.

future

imaginary

special

second conditional

If we went to France this summer, we could visit Pierre.

future

tentative

special

second conditional

Were we to offer you the job, would you be interested?

future

tentative

special

second conditional (alternatives to if)

Imagine / Supposing you could do any job you wanted. What would you do?

future

imaginary

special

second conditional (alternatives to if)

If I had gone to bed earlier, I wouldn't have overslept.

past

unreal

special

third conditional

If we had not booked early, we wouldn't have got tickets.

past

unreal

special

third conditional

Had I known you were asleep, I wouldn't have called.

past

unreal

special

third conditional (alternatives to if)

Imagine / supposing you had believed him. You would have lost all your money.

past

unreal

special

third conditional (alternatives to if)

If I had gone to bed earlier, I wouldn't be so sleepy now.

past / present

unreal

special

mixed conditional

Conditional sentences can be made without if

Conditionals with other words instead of if

Should you see Peter, could you ask him to call me.
If you see Peter, could you ask him to call me.
Supposing you lost your job, what would you do?
If you lost your job, what would you do?
Imagine you could live anywhere you liked. Where would you go?
If you could live anywhere you liked. where would you go?

Conditionals with inverted structures instead of if

Were he to refuse, you would be in a difficult position.
If he refused, you would be in a difficult position.
Had she known about the noise, she wouldn't have moved in.
If she had known about the noise, she wouldn't have moved in.

See individual pages on first, second and third conditionals for more details.

You can change the position of the clauses

The position of the clauses can be changed* without changing the meaning of the sentence :

If I have time, I'll give you a call.
I'll give you a call if I have time.
The two sentences have the same meaning.

*This is true for conditionals made with if, and those with without if where an inverted structure is used (Had I known... Were you to go).
It does not apply to conditionals made with suppose and imagine where two sentences are formed.

Punctuation in conditional sentences

When the if-clause comes first, it is followed by a comma; when the result clause comes first, there is no comma. This is because the if-clause is a dependent (or subordinate) clause. Dependent clauses are usually followed by a comma when they come before the main clause.

Pronunciation with conditional sentences

Conditional sentences are often long and include a number of auxiliary verbs such as have and been. For this reason, it is important to make use of contractions and stress when speaking.

Contractions with conditionals

It is normal in spoken English to contact subject pronouns and auxiliaries.
If she had not seen him, she would not have known he was there.
This becomes: If she hadn't seen him, she wouldn't've known he was there.

Stress with conditionals

Syllable and word stress are essential with longer, more complex sentences such as conditionals. If you give every word equal stress, it will be more difficult to understand and tiresome to say.
In normal spoken English, the example above sounds like this:

If she HADn't SEEN 'im, she WOULDntov known 'e was THERE.

Generally speaking, the following elements are stressed: negative auxiliaries (hadn't, didn't, not etc.), main verbs in affirmative (positive) sentences, nouns, and the words at the end of clauses (but not pronouns).

If I see Peter, I'll tell him about the party.
If you've finished your homework, you can watch TV.
If we had some money, we could get a taxi.
If I found some money in the street, I'd keep it.
If I don't hear from you, I'll assume you're coming.
If he wasn't rich, he wouldn't be famous.
If they hadn't made such a mess, I wouldn't have been so angry.
If she hadn't promised to keep it a secret, I wouldn't have told her.