The zero conditional is one of the basic types of conditionals, and it’s used to talk about general truths and real situations. In this guide, we’ll explain everything you need to know about the zero conditional, using simple language and plenty of examples. We’ll also provide exercises to help you practise. Let’s get started!

What is the Zero Conditional?

The zero conditional is used to talk about facts, general truths, and situations that are always true if something else happens. It describes what happens in real-life situations.

For example:

• If you heat water to 100 degrees Celsius, it boils.

In this sentence, both clauses are in the present simple tense, and the result is always true when the condition is met.

How to Form the Zero Conditional

Structure

The zero conditional follows this structure:

• If + present simple, present simple

Examples:

• If you mix red and blue, you get purple.
• If it rains, the ground gets wet.

You can also reverse the order of the clauses:

• Present simple + if + present simple

Examples:

• The ground gets wet if it rains.
• Plants die if they don’t get enough water.

Note: When starting with the “if” clause, use a comma to separate the clauses. When starting with the main clause, the comma is not necessary.

Using “If” and “When”

In the zero conditional, “if” and “when” can often be used interchangeably because the result is always the same.

Examples:

• If you freeze water, it turns into ice.
• When you freeze water, it turns into ice.

Both sentences express a general truth.

When to Use the Zero Conditional

General Truths

Use the zero conditional to talk about things that are generally true.

Examples:

• If you don’t water plants, they die.
• If you eat too much sugar, you gain weight.

Scientific Facts

Use it for scientific facts or laws of nature.

Examples:

• If you drop an object, it falls to the ground.
• If the sun sets, it gets dark.

Habits and Routines

Use it to describe habits or routines.

Examples:

• If I wake up early, I go for a run.
• If she has time, she reads the newspaper.

Instructions and Commands

You can use the zero conditional to give instructions or commands.

Structure:

• If + present simple, imperative

Examples:

• If you need help, call me.
• If he finishes his homework, let him play outside.

Examples of the Zero Conditional

Here are more examples to help you understand how the zero conditional is used:

• If you press this button, the machine stops.
• If it snows, the roads become slippery.
• People get nervous if they speak in public.
• Metal expands if it is heated.
• If you don’t eat, you feel hungry.

Common Mistakes and How to Avoid Them

Using Future Tense Instead of Present Simple

Mistake:

• If you will heat ice, it will melt.

Correction:

• If you heat ice, it melts.

Explanation: In the zero conditional, both clauses should be in the present simple tense.

Using “Would” or “Could”

Mistake:

• If you mix red and yellow, you would get orange.

Correction:

• If you mix red and yellow, you get orange.

Explanation: Do not use modal verbs like “would” or “could” in the zero conditional.

Confusing Zero Conditional with First Conditional

Mistake:

• If it rains, I will take an umbrella.

Explanation: This is a first conditional sentence, not a zero conditional. The zero conditional talks about general truths, while the first conditional talks about real possibilities in the future.

Zero Conditional Example:

• If it rains, the ground gets wet.

Forgetting to Use Present Simple in Both Clauses

Mistake:

• If you eat too much, you are getting sick.

Correction:

• If you eat too much, you get sick.

Explanation: Both clauses should be in the present simple tense.

Exercises

Let’s practise what you’ve learned!

Exercise 1: Fill in the Blanks

Use the correct form of the verbs in brackets to complete the zero conditional sentences.

1. If you ________ (heat) metal, it ________ (expand).
2. Plants ________ (die) if they ________ (not get) enough water.
3. If he ________ (eat) peanuts, he ________ (get) sick.
4. Water ________ (freeze) if the temperature ________ (drop) below zero.
5. If you ________ (mix) blue and yellow, you ________ (make) green.
6. I ________ (feel) tired if I ________ (not sleep) well.
7. If she ________ (drink) coffee, she ________ (not sleep) at night.
8. They ________ (be) happy if they ________ (win) the game.
9. If the phone ________ (ring), I ________ (answer) it.
10. Ice ________ (melt) when it ________ (be) heated.

Answers:

1. If you heat metal, it expands.
2. Plants die if they don’t get enough water.
3. If he eats peanuts, he gets sick.
4. Water freezes if the temperature drops below zero.
5. If you mix blue and yellow, you make green.
6. I feel tired if I don’t sleep well.
7. If she drinks coffee, she doesn’t sleep at night.
8. They are happy if they win the game.
9. If the phone rings, I answer it.
10. Ice melts when it is heated.

Exercise 2: Rewrite the Sentences

Rewrite the following sentences as zero conditional sentences.

1. People feel happier when the sun shines.

Answer: If the sun shines, people feel happier.

2. When you cross the street without looking, you might have an accident.

Answer: If you cross the street without looking, you have an accident.

3. Heat ice, and it turns into water.

Answer: If you heat ice, it turns into water.

4. Dogs bark when they see strangers.

Answer: If dogs see strangers, they bark.

5. The alarm rings when it detects smoke.

Answer: If it detects smoke, the alarm rings.

Exercise 3: Create Your Own Sentences

Create zero conditional sentences based on the prompts.

1. (If / you / not eat / you / be / hungry)

Answer: If you don’t eat, you are hungry.

2. (If / it / rain / plants / grow)

Answer: If it rains, plants grow.

3. (If / you / study / you / learn)

Answer: If you study, you learn.

4. (If / I / wake up / late / I / miss / the bus)

Answer: If I wake up late, I miss the bus.

5. (If / water / reach / 100 degrees Celsius / it / boil)

Answer: If water reaches 100 degrees Celsius, it boils.

Conclusion

Understanding the zero conditional is essential for expressing general truths, scientific facts, habits, and instructions in English. Remember:

• The zero conditional uses the present simple tense in both clauses.
• It describes situations that are always true if the condition is met.
• “If” and “when” can often be used interchangeably in zero conditional sentences.

Keep practising with the exercises provided, and try creating your own sentences to improve your understanding.

If you have any questions, thoughts, or if you’d like to share your own sentences using the zero conditional, please leave a comment below. Happy learning!