Third Conditional

• CEFR B2
• Grammar
• Printable
• Answer key

Third Conditional is a printable grammar worksheet for English language learners at CEFR level B2. It covers imagined past situations and regrets, with 5 exercises and an answer key.

We use the third conditional to talk about imaginary past situations — things that did NOT happen. It expresses regret, relief, or speculation about how the past could have been different.

The if-clause uses the past perfect (had + past participle). The main clause uses would have / could have / might have + past participle.

We can vary the modal in the main clause: 'would have' for certain hypothetical results, 'might have' for uncertain possibilities, and 'could have' for ability or permission that didn't happen.

Examples

• If I had known about the traffic, I would have left earlier.
• She wouldn't have failed if she had revised properly.
• If they had arrived on time, we might have caught the flight.
• He could have helped if you had asked him.
• If I hadn't taken that job, I would never have met my partner.
• We would have got lost if we hadn't had a map.
• If she had followed the doctor's advice, she might have recovered faster.
• Would you have come if I had invited you?

What's in this worksheet

1. Complete with the correct form
2. Correct the mistake
3. Complete with your own main clause
4. Write the sentence
5. Mixed gap fill

Common mistakes

• If I would have studied, I would have passed.  →  If I had studied, I would have passed. Never use 'would have' in the if-clause. Use the past perfect (had + past participle).
• If she didn't come, I would have been upset.  →  If she hadn't come, I would have been upset. Third conditional if-clause requires past perfect ('hadn't come'), not past simple ('didn't come').
• I would have to go if he had called.  →  I would have gone if he had called. 'Would have to go' confuses obligation with the conditional. The third conditional uses 'would have + past participle'.
• They might have won if they played better.  →  They might have won if they had played better. Both clauses need the correct form: if-clause = past perfect, result = modal + have + past participle.

Speaking prompts

• Think of a decision you made in the past. How would your life be different if you had decided differently?
• Imagine a famous historical event. What would have happened if it had gone differently?
• Have you ever missed an opportunity (a trip, a job, a meeting)? What would have happened if you hadn't missed it?
• Think of a mistake you or someone you know made. What would you have done differently?