Conditionals: zero, first and second

Conditionals: zero, first and second

Do you know how to use the zero, first and second conditionals? Test what you know with interactive exercises and read the explanation to help you.

Look at these examples to see how zero, first and second conditionals are used.

If you freeze water, it becomes solid.
If it rains tomorrow, I'll take the car.
If I lived closer to the cinema, I would go more often.

Try this exercise to test your grammar.

Grammar test 1

Conditionals 1: Grammar test 1

Read the explanation to learn more.

Grammar explanation

Conditionals describe the result of a certain condition. The if clause tells you the condition (If you study hard) and the main clause tells you the result (you will pass your exams). The order of the clauses does not change the meaning.

If you study hard, you will pass your exams.
You will pass your exams if you study hard.

Conditional sentences are often divided into different types.

Zero conditional

We use the zero conditional to talk about things that are generally true, especially for laws and rules.

If I drink too much coffee, I can't sleep at night.
Ice melts if you heat it.
When the sun goes down, it gets dark.

The structure is: if/when + present simple >> present simple.

First conditional

We use the first conditional when we talk about future situations we believe are real or possible.

If it doesn't rain tomorrow, we'll go to the beach.
Arsenal will be top of the league if they win.
When I finish work, I'll call you.

In first conditional sentences, the structure is usually: if/when + present simple >> will + infinitive. 

It is also common to use this structure with unless, as long as, as soon as or in case instead of if.

I'll leave as soon as the babysitter arrives.
I don't want to stay in London unless I get a well-paid job.
I'll give you a key in case I'm not at home.
You can go to the party, as long as you're back by midnight.

Second conditional

The second conditional is used to imagine present or future situations that are impossible or unlikely in reality.

If we had a garden, we could have a cat.
If I won a lot of money, I'd buy a big house in the country.
I wouldn't worry if I were you.

The structure is usually: if + past simple >> + would + infinitive. 

When if is followed by the verb be, it is grammatically correct to say if I were, if he were, if she were and if it were. However, it is also common to hear these structures with was, especially in the he/she form.

If I were you, I wouldn't mention it.
If she was prime minister, she would invest more money in schools.
He would travel more if he was younger.

Do this exercise to test your grammar again.

Grammar test 2

Conditionals 1: Grammar test 2

Language level

Average: 4.1 (281 votes)

Submitted by lean on Sat, 22/05/2021 - 10:33

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Hello :-) I saw you use (have to use) present simple too in main clause, if you use "unless", "as long as", "as soon as" or "in case" instead of if for the first conditional. If I were you, I'd correct the common rule for the first conditional (if/when + present simple >> will + infinitive. ) :-))))))))))))))))))))) Best regards
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Submitted by Kirk Moore on Sat, 22/05/2021 - 14:34

In reply to by lean

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Hello lean,

Thanks for your suggestion. We actually considered that, but decided to try to keep the page simple and so did not include that information. 

Thanks again!

Best wishes,

Kirk

The LearnEnglish Team

Submitted by Ayn on Mon, 15/03/2021 - 06:12

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A)Unless people stick to their diets, they will face obesity problems more than ever. B)Unless people stick to their diets, they face obesity problems more than ever. Which looks correct?

Hello Ayn,

I would recommend that you not use 'unless' here. 'unless' means something like 'if ... not', but only when it expresses an idea like 'except if'. If we reword the sentence as 'Except if people stick to their diets ...', it seems awkward.

In comparison, 'If people do not stick to their diets' seems more straightforward to me, and in this case you could say 'they face' to refer to a generally-known fact or 'they will face' to make a prediction.

I'd recommend you have a look at this Cambridge Grammar page on Unless, which has lots of useful example sentences.

Hope this helps.

All the best,

Kirk

The LearnEnglish Team

Since I'm predicting they will face obesity more than ever, should I use first conditional?

Hello Ayn,

Yes, the first conditional would be better if you are making a prediction.

All the best,

Kirk

The LearnEnglish Team

Submitted by ValerieP on Wed, 24/02/2021 - 06:45

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Hello Peter, Could you please clarify why we use present simple in both parts of the first conditional sentences if it's not a modal verb, a going to or an imperative structure in a result part, for example "I don't want to stay in London unless I get a well-paid job" Thanks in advance!

Hello ValerieP,

In the if-clause (here, unless has the meaning 'if not'), we use a present form, so this is normal. The result clause normally refers to a likely or expected future result and uses a modal verb such as will:

I won't stay in London unless I get a well-paid job.

Other modal verbs can be used as well: might, can, should etc.

 

However, there are some verbs which express present attitudes towards the future which we can use in the result clause. Want is one of these:

I don't want to stay in London unless I get a well-paid job.

Other verbs like this include hope, expect, plan and intend. I'm sure you can see the semantic similarities here.

 

Peter

The LearnEnglish Team

Submitted by gsgxxiii on Wed, 17/02/2021 - 09:17

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Let's say, I have something that I rarely use, but I don't want to throw it away because I think I may need it in the future. So, do I use conditional 1 or 2? I thought I should keep it just in case I needed to use it. I thought I should keep it just in case I need to use it.

Hi gsg238,

Both are possible! It depends how likely you think you are to need it. Using the first conditional (in case I need to use it) means that you think there is a reasonable chance that you will need it. Using the second conditional (in case I needed to use it) means that you see this as unlikely to happen.

Best wishes,

Jonathan

The LearnEnglish Team