Third Conditional
The Third Conditional describes hypothetical situations in the past — things that did not happen, and imagines different outcomes. It expresses regret, criticism, or relief about past events. The structure is: If + past perfect, would have + past participle.
WHEN TO USE
Use to talk about past situations that did NOT happen, and imagine what the result WOULD HAVE BEEN. Common for expressing regret, criticism of past actions, or imagining alternative outcomes.
STRUCTURE
If + past perfect, would have + past participleIf I had studied harder, I would have passed the exam.
If + past perfect, wouldn't have + past participleIf they had taken a taxi, they wouldn't have missed the flight.
Would S + have + past participle + if + past perfect?Would she have called you if she had known your number?
SIGNAL WORDS
- if
- would have
- could have
- might have
- had (done)
EXAMPLES
If I had studied harder, I would have passed the exam.
She would have called you if she had known your number.
If they had taken a taxi, they wouldn't have missed the flight.
I would have helped you if you had asked me.
He might have got the job if he had arrived on time.
COMMON MISTAKES
If I would have studied harder, I would have passed.
If I had studied harder, I would have passed.
In the if-clause, use past perfect (had + past participle) — NOT 'would have'
She would have pass the exam if she had studied.
She would have passed the exam if she had studied.
After 'would have', use the past participle form (passed, not pass)
Tip
Third conditional = regret or imagining the past differently. Both parts are in the past: If + HAD done (past perfect) → WOULD HAVE done (past result). Nothing can change — it's all hypothetical!