What is the first conditional in English?

The first conditional describes a possible situation in the future and its likely result. It follows the formula: If + present simple, will + base verb. For example: 'If it rains tomorrow, I will take an umbrella.' The condition is possible, not guaranteed.

What is the difference between first and second conditional?

The first conditional talks about real and possible future situations (If I study, I will pass). The second conditional talks about unreal or hypothetical situations (If I studied, I would pass). First conditional uses present simple + will. Second conditional uses past simple + would.

Can I use 'unless' in first conditional sentences?

Yes. 'Unless' means 'if not.' You can replace 'if not' with 'unless' in first conditional sentences. For example: 'Unless it rains, we will go to the beach' means the same as 'If it does not rain, we will go to the beach.' Use 'unless' with a positive verb.

What other modals can I use instead of 'will' in the first conditional?

You can use 'can,' 'might,' 'should,' or 'must' instead of 'will' in first conditional sentences. Each changes the meaning slightly. 'If you finish early, you can leave' (permission). 'If it rains, we might stay home' (possibility). 'If you want to pass, you must study' (obligation).

Can the if-clause come at the end of the sentence?

Yes. You can put the if-clause at the beginning or the end of a first conditional sentence. When it comes first, use a comma. When it comes second, no comma is needed. 'I will call you if I arrive late' and 'If I arrive late, I will call you' are both correct.

Is 'when' the same as 'if' in first conditional sentences?

No. In the first conditional, 'when' and 'if' have different meanings. 'If' means the situation is possible but not certain. 'When' means you are sure the situation will happen. Compare: 'If I see him, I will say hello' (I might or might not see him). 'When I see him, I will say hello' (I am certain I will see him).

Guide · Updated 2026 07

First Conditional: Rules, Examples, and Practice

Learn the first conditional in English. Clear formula for possible future situations, examples, common mistakes, and practice with answer key.

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Grammar Guide · Updated July 2026

Use the first conditional to talk about real and possible future situations. If you study this guide, you will understand how to form and use first conditional sentences correctly.

Quick Reference

Formula: If + present simple, will + base verb

Use for: Real and possible future situations, promises, warnings, plans

Example: "If you study hard, you will pass the exam."

What Is the First Conditional?

The first conditional is a sentence structure used to talk about a possible future situation and its likely result. The condition is real and could happen. Unlike the zero conditional (which talks about things that are always true), the first conditional talks about specific future possibilities.

Think of it this way: A condition exists (the if-clause), and if that condition is met, a specific result will follow (the result clause). The speaker believes both are possible.

English learners use the first conditional every day for making promises, giving warnings, making plans, and talking about consequences.

The Formula

If + subject + present simple verb, subject + will + base verb

You can also reverse the order. When the if-clause comes second, no comma is needed:

Subject + will + base verb + if + subject + present simple verb

With comma: If you study, you will pass.

Without comma: You will pass if you study.

When to Use the First Conditional

1. Real Future Possibilities

Use the first conditional when you talk about something that is likely to happen in the future. The situation is realistic and possible.

If it rains tomorrow, we will stay home.
If she studies for the test, she will get a good score.
If the train is late, I will take a taxi.
If they invite us, we will go to the party.
If you book early, you will get a discount.

2. Promises and Offers

Use the first conditional to make promises or offers. You commit to doing something if a condition is met.

If you help me with this project, I will buy you lunch.
If you come to the party, I will introduce you to my friends.
If he finishes his homework, I will take him to the park.
If you need a ride, I will pick you up.
If she calls, I will tell her the news.

3. Warnings and Threats

The first conditional is commonly used for warnings. It tells someone what will happen if they do (or do not do) something.

If you touch that wire, you will get a shock.
If you do not wear a coat, you will catch a cold.
If you drive too fast, you will get a ticket.
If you leave the door open, the cat will escape.
If you do not pay the bill, they will cut off your electricity.

4. Plans and Arrangements

Use the first conditional to discuss plans that depend on certain conditions being met.

If the weather is nice, we will have a barbecue.
If I get the job, I will move to London.
If the boss agrees, we will start the project next week.
If you are free on Saturday, we will go hiking.
If they approve the budget, we will hire a new teacher.

Using Other Modals in the First Conditional

While 'will' is the most common modal verb in the result clause, you can use other modals to express different meanings.

Modal	Meaning	Example
can	Permission or ability	If you finish early, you can leave.
might	Possibility (not certain)	If it rains, we might stay home.
should	Advice or recommendation	If you feel sick, you should see a doctor.
must	Obligation or necessity	If you want to pass, you must study.

Common Mistakes with First Conditional

Mistake 1: Using 'will' in the if-clause

Incorrect: If I will have time, I will help you.

Correct: If I have time, I will help you.

Mistake 2: Using 'would' instead of 'will' in the result clause

Incorrect: If it rains, I would stay home.

Correct: If it rains, I will stay home.

Mistake 3: Confusing first conditional with zero conditional

Zero conditional (general truth): If you heat ice, it melts.

First conditional (specific future): If you heat this ice, it will melt.

Practice Exercises

Complete each sentence with the correct form of the verb in brackets.

If she _______ (study) harder, she will pass the exam.
If they _______ (arrive) late, the teacher will be angry.
We _______ (go) to the beach if the weather is nice.
If you _______ (not water) the plants, they will die.
He _______ (not get) the job if he does not prepare for the interview.
If I _______ (have) enough money, I will buy a new phone.
They _______ (be) happy if you visit them.
If we _______ (leave) now, we will catch the train.

Answer Key

studies
arrive
will go
do not water
will not get
have
will be
leave

Practice with a Real Teacher

The best way to master conditionals is through conversation practice. A tutor can correct your mistakes in real time and help you use first conditional naturally in everyday speech.

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