The Zero Conditional – Present Real Conditional.
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What is the zero conditional?
- Zero conditional is easy to form because all the verbs are in present tense. You just use two clauses, one with If + simple present verb and the other with another simple present verb:
If + Present Simple, …. Present Simple.
If you freeze water, it turns into ice.
And, if you heat water at 100 degrees, it boils.
If students miss an exam, the professor fails them.
- You can reverse the order of the clauses. If the “if” clause comes first, a comma is usually used. If the “if” clause comes second, there is no need for a comma.
The professor fails students if they miss an exam.
I get tired if I work too much.
- We often use the imperative or the modal verb in the main clause when we give some advice or instructions.
If I’m late for dinner, start eating without me.
- The ‘if‘ in this conditional can usually be replaced by ‘when‘ without changing the meaning.
When people eat too much, they get fat. (= If people eat too much, they get fat.)
- ‘Unless‘ means the same as ‘if not‘.
Unless he asks you politely, refuse to do any more work on the project. (= If he doesn’t ask you politely, refuse to do any more work on the project.)
How to use the zero conditional
The zero conditional is is used for actual facts, scientific events, things which are always true.
If you heat ice, it melts.
If you cross an international date line, the time changes.
And, if public transport is efficient, people stop using their cars.
If my wife has a cold, I usually catch it.