Grammar Booster:
Zero Conditionals
Zero Conditionals are used to describe general truths, scientific facts, and things that always happen when a certain condition is met. They’re perfect for explaining how things work — machines, nature, habits, and rules.
Zero Conditional: Structure
The Zero Conditional uses the present simple tense in both clauses:
| Affirmative | Negative | Interrogative |
|---|---|---|
| If I press this, it starts. | If I don’t press this, it doesn’t start. | If I press this, does it start? |
| If you press this, it starts. | If you don’t press this, it doesn’t start. | If you press this, does it start? |
| If he presses this, it starts. | If he doesn’t press this, it doesn’t start. | If he presses this, does it start? |
| If she presses this, it starts. | If she doesn’t press this, it doesn’t start. | If she presses this, does it start? |
| If it presses this, it starts. | If it doesn’t press this, it doesn’t start. | If it presses this, does it start? |
| If we press this, it starts. | If we don’t press this, it doesn’t start. | If we press this, does it start? |
| If they press this, it starts. | If they don’t press this, it doesn’t start. | If they press this, does it start? |
*“This” = a button | “It” = a machine
📘 Grammar Rule
Zero Conditional = if + present simple, … present simple
We use it for facts or things that are always true when the condition happens.
b) If you leave chocolate in the hot sun, it melts.
When to Use Zero Conditionals
1. To Describe Habits or General Truths
• If I work on the computer too much, my eyes start to hurt.
2. With “When” = “Every Time”
You can often replace if with when to mean “every time that”.
• When I’m sad, I like to go shopping.
3. With Imperatives (Instructions)
• When you’re ready, call me!
4. With Other Tenses & Modals
- Present Continuous: If they’re trying to work, don’t make too much noise.
- Present Perfect: When you’ve finished that, let me know.
- Modal Verbs: If I drink too much coffee, I can’t sleep at night.
💬 Dialogue: The New Employee
Nigel has just started work in a factory. He’s talking to his boss, Bruce. Listen and complete the blanks.
Bruce: You must be the new guy. I’m Bruce Gorkins, the shop floor manager.
Nigel: Hi, I’m Nigel. Pleased to meet you.
Bruce: Pleased to meet you. So, I just need to go over a few things. Basically, your job consists of putting toys into (1).
Nigel: OK.
Bruce: You need to put three toys into each box and then close it with tape. It takes about 10 seconds to do, so you’ve got plenty of (2).
Nigel: All right.
Bruce: If you forget to pack the box, it goes down the chute without any (3) in it. So, you’ve got to concentrate.
Nigel: All right.
Bruce: If you need to pause the machine, press this yellow (4). And if you go to the toilet, write down when you went and how long you took in this little (5).
Nigel: OK.
Bruce: Don’t touch this red button. If you press it, the (6) stops and it’s really hard to re-set. OK?
Nigel: All right.
Bruce: So, remember, press the yellow button if you want to pause it, but don’t touch the red button.
Nigel: OK.
Bruce: Right, well, then I’ll turn the machine on, and you can get started. I’ll be back in a couple of (7) to see how you’re getting on. Good luck!
Nigel: OK. Thanks. [The machine starts, the manager leaves and the boxes start coming down the conveyor belt.] Right, toys in: one, two. Close the box. This is easy! Oh, wait a minute, it was supposed to be three. Erm, to stop the (8), press the… the red button. Yes, the red button. OK. Here goes. [He presses the red button. An alarm goes off.] Hello? Hello? Help!
💡 Suggested Answers (for reference)
- boxes
- time
- toys
- button
- notebook
- machine
- hours
- machine
🎓 Pro Tip: Use Zero Conditionals Naturally
Practice giving instructions or explaining everyday facts using if or when. For example:
- If you heat water to 100°C, it boils.
- When the phone rings, I answer it.
- If you don’t water plants, they die.
These structures are common in workplaces, manuals, and daily conversation — master them to sound more fluent!
