The Zero Conditional is used to express situations where the outcome is always true, like scientific facts or general truths. It describes real and factual situations with predictable results.
Structure of the Zero Conditional
The Zero Conditional follows this pattern:
Part 1 Part 2 If + present simple present simple
You can also reverse the order:
Part 1 Part 2 Present simple if + present simple
Examples of the Zero Conditional
Scientific Facts
- If you heat water to 100 degrees Celsius, it boils.
- If you mix blue and yellow, you get green.
- Plants die if they don’t get water.
General Truths
- If you don’t eat, you get hungry.
- If it rains, the ground gets wet.
- Ice melts if you heat it.
Instructions and Procedures
- If you press this button, the machine starts.
- If you want good results, you practice every day.
Important Notes
- We use the present simple tense in both parts of the Zero Conditional.
- The “if” in this conditional can often be replaced with “when” without changing the meaning.
- Unlike other conditionals, the Zero Conditional does not use a comma between the two clauses when the “if clause” comes first.
Using “When” Instead of “If”
In the Zero Conditional, “if” and “when” are often interchangeable:
- If you heat ice, it melts.
- When you heat ice, it melts.
Both sentences have the same meaning in this context.
Zero Conditional vs. First Conditional
| Zero Conditional | First Conditional |
|---|---|
| For facts and things that are generally true | For possible future situations |
| If + present simple, present simple | If + present simple, will + infinitive |
| If you heat water, it boils. | If it rains tomorrow, I will stay home. |
| If you don’t sleep, you feel tired. | If I don’t sleep tonight, I will feel tired tomorrow. |
Common Mistakes to Avoid
- Using future tense in the result clause:
- ❌ If you heat water to 100°C, it will boil. (This is First Conditional)
- ✓ If you heat water to 100°C, it boils. (Zero Conditional)
- Using a comma when the if-clause comes first:
- ❌ If you don’t eat, you get hungry.
- ✓ If you don’t eat you get hungry.
Review
The Zero Conditional is used for:
- Scientific facts
- General truths
- Things that always happen in certain situations
Structure: If + present simple, present simple
Key points to remember:
- Both clauses use the present simple tense
- The result is always true when the condition happens
- “If” can often be replaced with “when”
Summary
The Zero Conditional is a fundamental grammatical structure in English that helps us express cause and effect relationships that are always true. By mastering this conditional form, you’ll be able to discuss scientific principles, general truths, and everyday facts with greater confidence and accuracy.