Simple explanation
What is a conditional sentence? A conditional sentence connects a condition with a result. The condition is often introduced by if. In “If it rains, we stay inside,” rain is the condition and staying inside is the result. At B1 level, it is important to go beyond memorizing formulas. You need to decide what the speaker means: Is this a general result, a real future possibility, or an imagined situation? Zero conditional: facts and regular results The zero conditional is used for general truths, rules, habits, and situations where a particular condition regularly produces the same result. In its basic form, both the if-clause and the result clause use the present simple. It normally describes what happens in general rather than one uncertain event in the future. First conditional: real future possibilities The first conditional is used when a future condition is realistically possible. Its basic pattern is if + present simple, followed by will + base verb in the result clause. For example, “If I finish early, I'll call you” means that finishing early is not certain, but the speaker sees it as a real possibility. Second conditional: hypothetical or unlikely situations The second conditional describes hypothetical, unreal, or less likely situations in the present or future. Its basic pattern is if + past simple, followed by would + base verb. The past simple does not necessarily refer to past time here. Instead, it creates distance from reality. “If I had more time, I would learn Spanish” usually suggests that the speaker does not have more time now. The main difference between the three conditionals Choose the conditional according to meaning first. Use the zero conditional when a result is generally or regularly true. Use the first conditional when you see a future condition as a realistic possibility. Use the second conditional when you imagine a different reality or see the situation as unlikely. The conditional therefore communicates the speaker's view of the situation, not only time. First conditional or second conditional? The difference between the first and second conditionals can depend on the speaker's perspective. Compare “If I get the job, I'll move to London” with “If I got a job in London, I would move there.” The first presents getting the job as a real possibility. The second creates more hypothetical distance. Different speakers may describe a similar situation differently depending on how realistic they think it is. Changing the order of the clauses The if-clause can come first or second without changing the basic meaning. Compare “If it rains, we'll stay home” and “We'll stay home if it rains.” When the if-clause comes first, it is normally followed by a comma. When it comes second, a comma is usually unnecessary. Negative forms and questions All three conditional types can contain negative forms. For example: “If you don't water plants, they die,” “If she doesn't hurry, she'll miss the bus,” and “If I didn't have to work, I would come with you.” Questions are also possible. “What will you do if it rains?” asks about a real future possibility, while “What would you do if you found a wallet?” asks the listener to imagine a hypothetical situation.
Grammar formula
Zero conditional
If + Present Simple, Present SimpleIf you heat ice, it melts.
First conditional
If + Present Simple, will + base verbIf it rains tomorrow, we'll stay home.
Second conditional
If + Past Simple, would + base verbIf I had more money, I would travel more.
Negative zero conditional
If + subject + don't/doesn't + base verb, Present SimpleIf you don't charge the battery, it runs out.
Negative first conditional
If + subject + don't/doesn't + base verb, subject + won't + base verbIf you don't leave now, you won't arrive on time.
Negative second conditional
If + subject + didn't + base verb, subject + wouldn't + base verbIf I didn't live so far away, I would visit more often.
First conditional question
Wh-word + will + subject + base verb + if + Present Simple?What will you do if you miss the train?
Second conditional question
Wh-word + would + subject + base verb + if + Past Simple?What would you do if you lost your phone?
Core rules
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Rule 1: Zero conditional
Use the zero conditional for general truths, rules, habits, and regular cause-and-result relationships. The basic structure is if + present simple, present simple.
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Rule 2: First conditional
Use the first conditional for a real or realistic future possibility. The basic structure is if + present simple, will + base verb. Although the condition refers to the future, the basic if-clause normally uses the present simple rather than will.
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Rule 3: Second conditional
Use the second conditional for hypothetical, unreal, or less likely situations in the present or future. The basic structure is if + past simple, would + base verb.
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Rule 4: Were in hypothetical situations
In hypothetical statements with be, were can be used with all subjects, especially in more standard or formal usage. The expression “If I were you” is particularly common when giving advice.
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Rule 5: Clause order
The if-clause can come before or after the result. “If I see Sara, I'll tell her” and “I'll tell Sara if I see her” express the same basic condition.
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Rule 6: Choose by meaning, not only form
Do not identify a conditional only by looking at one verb. First decide whether the speaker is expressing a general result, a realistic future possibility, or a hypothetical situation.
Useful examples
If you mix blue and yellow, you get green.
Mixing blue and yellow produces green.
This is the zero conditional because it describes a general result.
If I drink coffee late at night, I can't sleep.
Drinking coffee late usually makes it difficult for me to sleep.
The zero conditional can describe a regular personal result, not only scientific facts.
If people don't get enough sleep, they often feel tired.
People often become tired when they do not sleep enough.
This describes a general relationship rather than one particular future event.
If you press this button, the screen turns off.
Pressing this button causes the screen to switch off.
The zero conditional is useful for describing how things normally work.
If it rains tomorrow, we'll cancel the picnic.
We will cancel the picnic if there is rain tomorrow.
This is the first conditional because rain is a real future possibility.
If I finish this report tonight, I'll send it to you.
I will send you the report if I manage to complete it tonight.
Finishing the report is uncertain but realistically possible.
If Sara doesn't leave soon, she'll miss her train.
Sara will miss the train unless she leaves soon.
The condition is negative, but the sentence still follows the first conditional pattern.
What will you do if they don't accept your application?
What is your plan if your application is rejected?
This question asks about a possible future event.
If I see Daniel at the meeting, I'll give him your message.
I will pass your message to Daniel if I meet him there.
Seeing Daniel is possible, but it is not certain.
If I had a bigger apartment, I would get a dog.
I would have a dog if my apartment were larger.
The speaker imagines living in circumstances different from the current ones.
If I were you, I would talk to the manager.
In your situation, my choice would be to speak to the manager.
“If I were you” is a common second conditional expression for giving advice.
If we lived closer to the office, we wouldn't need a car.
Living nearer the office would remove our need for a car.
A hypothetical condition is combined with a negative result.
What would you buy if you won a million dollars?
Imagine winning a million dollars: what would you choose to buy?
The question invites the listener to imagine a hypothetical situation.
If I knew the answer, I would tell you.
I would give you the answer if I knew it.
The second conditional strongly suggests that the speaker does not know the answer.
I'll call you if I hear any news.
I will phone you if I receive any new information.
The if-clause comes second, so a comma is normally not needed.
Common mistakes
- ❌ If it will rain tomorrow, we'll stay home. ✅ If it rains tomorrow, we'll stay home. In the basic first conditional, use the present simple in the if-clause even though the condition refers to the future.
- ❌ If I will have time, I will call you. ✅ If I have time, I will call you. A normal future condition after if takes the present simple in the first conditional.
- ❌ If I would have more money, I would travel more. ✅ If I had more money, I would travel more. In the basic second conditional, the if-clause uses the past simple and would is used in the result clause.
- ❌ If I have a million dollars, I would buy a house. ✅ If I had a million dollars, I would buy a house. If the speaker means a hypothetical situation, the verb forms should follow the second conditional pattern.
- ❌ If you heat water to 100°C, it will boil. ✅ If you heat water to 100°C, it boils. When the purpose is to state a general fact, the zero conditional with the present simple in both clauses is the more appropriate basic pattern.
- ❌ If I was you, I would apologize. ✅ If I were you, I would apologize. “If I were you” is the standard and widely used hypothetical expression for giving advice.
- ❌ If she studied harder, she will pass the exam. ✅ If she studied harder, she would pass the exam. When the condition is presented as hypothetical, past simple in the if-clause is normally paired with would + base verb in the result.
Learning tips
- Ask yourself one question before choosing a form: Is this generally true, realistically possible, or hypothetical?
- Think of the zero conditional as “whenever this happens, this is the normal result.”
- The first conditional refers to the future, but its basic if-clause uses the present simple.
- In the second conditional, the past simple often expresses distance from reality rather than past time.
- Use “If I were you, I would ...” as a useful B1 pattern for giving advice.
- Put a comma after the if-clause when it comes first. A comma is normally unnecessary when the if-clause comes second.
- The same situation can sometimes be expressed with the first or second conditional depending on the speaker's view of how realistic it is.
Practise this topic
Interactive exercises for this topic are coming soon.
PlannedRelated grammar
Related dictionary words
Frequently asked questions
Why do we use the present simple after if when the first conditional is about the future?
In the standard first conditional pattern, the if-clause uses the present simple to express the future condition. We normally put will in the result clause: “If she calls, I'll tell you.”
Does the past simple in the second conditional refer to the past?
Not necessarily. In the second conditional, the past simple often signals hypothetical distance rather than past time. For example, “If I had more time” can describe the speaker's present situation.
How can I choose between the first and second conditional?
Think about how you view the condition. If you see it as a realistic future possibility, the first conditional is usually appropriate. If you are imagining it or consider it unlikely, the second conditional is usually more suitable.
Can the same situation be expressed with both the first and second conditional?
Yes, if the speaker's perspective changes. “If I get the job, I'll move” treats getting the job as a real possibility. “If I got the job, I would move” creates more hypothetical distance.
Should I say “If I was you” or “If I were you”?
“If I were you” is the standard expression for hypothetical advice and is the safest form to use. “If I was” can occur in informal speech, but “If I were you” is the established pattern learners should master.
Can the if-clause come at the end of the sentence?
Yes. Both “If I see him, I'll tell him” and “I'll tell him if I see him” are correct. When the if-clause comes second, a comma is normally not used.
Do I always have to use will in the result clause of the first conditional?
Will is the core B1 pattern and should be mastered first, but it is not the only possible form. Depending on the meaning, the result can also contain a modal verb or an imperative. The basic contrast between the conditionals still depends on the meaning of the condition.