Conditionals – Grammar
1. Form
| Type | If-clause (condition) | Main clause (result) |
|---|---|---|
| 0 | present simple | present simple |
| 1 | present simple | will + base verb |
| 2 | past simple | would + base verb |
| 3 | past perfect | would have + past participle |
| Mixed | past perfect | would + base verb |
2. Form – Details
| Type | Affirmative | Negative | Interrogative |
|---|---|---|---|
| 0 | If you heat water, it boils. | If you don’t water plants, they die. | What happens if you heat ice? |
| 1 | If it rains, I’ll stay home. | If I don’t study, I won’t pass. | Will you come if I invite you? |
| 2 | If I were rich, I’d travel. | If he didn’t smoke, he’d feel better. | What would you do if you won? |
| 3 | If I had studied, I’d have passed. | If she hadn’t forgotten, she’d have called. | What would you have done if you had known? |
| Mixed | If I had studied, I’d be a doctor now. | If you hadn’t lied, we would trust you. | What would you do now if you had taken the job? |
3. Use
Type 0 – General truths
- Situation: always true, scientific or general facts.
- Example: If you touch fire, it burns.
Type 1 – Real future possibility
- Situation: possible and likely condition in the future.
- Example: If you study, you will pass.
Type 2 – Unreal present
- Situation: imaginary or unlikely situation now.
- Example: If I had a car, I would drive to the beach.
Type 3 – Unreal past
- Situation: past event didn’t happen, imagining different outcome.
- Example: If I had set an alarm, I wouldn’t have been late.
Mixed – Unreal past → Present result
- Situation: past event that affects the present.
- Example: If I had taken the train, I would be home now.
4. Remarques
- “If I were” est préféré à “If I was” dans un registre formel, surtout dans les phrases imaginaires.
- “Would” n’est jamais utilisé dans la subordonnée “if”.
- On peut remplacer “if” par “unless”, “as long as”, “provided that”, etc. pour varier.