Grammar Focus: Third Conditional

The Third Conditional talks about unreal/hypothetical past situations and their imaginary past results — a situation that did NOT happen, and what would have followed.

Form: If + Past Perfect, would have + past participle (V3). (Also: might have / could have for possibility/ability.)

Examples: If a large asteroid had hit Earth, it would have caused massive devastation. If scientists had known in advance, they might have been able to warn people.

Second vs. Third: Second = unreal present/future (If I had money, I would buy a car); Third = unreal past (If I had had money, I would have bought a car).