Conditional Type 3

What is Conditional Type 3?

We use the Third Conditional to talk about impossible situations in the past. We use it to describe a past that did not happen, and to imagine a different result.

It is very common when expressing regret or criticizing a past action.

If I had studied harder, I would have passed the exam.
(Reality: I didn't study hard, so I failed.)

If she had known you were here, she would have called you.
(Reality: She didn't know, so she didn't call.)

Structure

The grammatical structure uses the Past Perfect and Would Have:

IF + Past Perfect + COMMA + WOULD HAVE + Past Participle

Examples:

• If I had left earlier, I would have caught the train.
• If it had rained, we would have stayed inside.

You can reverse the order. If the "IF" clause comes second, do not use a comma:

WOULD HAVE + Past Participle + IF + Past Perfect

I would have caught the train if I had left earlier.

Spoken English

In spoken English, we often contract had and would to 'd. Be careful, as the sound is the same, but the grammar is different:

• If I'd known... (= If I had known)
• I'd have gone... (= I would have gone)