Conditionals Made Clear
Four structures, four levels of reality — from scientific facts to impossible pasts. Here's how to tell them apart.
🔄 The 4 Main Types
0Zero Conditional
If + present simple → present simple
General truths, facts, things that always happen.
If you heat ice, it melts. • Water boils if you heat it to 100°C.
1First Conditional
If + present simple → will + base verb
Real, possible situations in the future.
If it rains tomorrow, we will cancel the picnic.
2Second Conditional
If + past simple → would + base verb
Unlikely or hypothetical situations, now or in the future.
If I won the lottery, I would travel the world. • If I were you, I'd apologise.
3Third Conditional
If + past perfect → would have + past participle
Impossible pasts — imagining a different outcome that didn't happen.
If she had studied harder, she would have passed the exam.
🔗 Connectors
💡 Beyond "if"
Unless = "if...not". Provided that / as long as = a formal/strict condition.
You'll miss the bus unless you hurry.
You can borrow it as long as you return it.
We'll sign provided that all terms are met.
Quick Reference
| Type | If-clause | Main clause |
|---|
| Zero | present simple | present simple |
| First | present simple | will + base verb |
| Second | past simple | would + base verb |
| Third | past perfect | would have + past participle |