THIRD CONDITIONAL

Form     If +past perfect + would have +past participle short form: 'd   (=had/would)

Uses

1. To talk about an event that did not happen because of the condition in the if clause. The third conditional is often used for excuses.
2. To talk about a condition that is unreal because it did not and could not happen.

Examples

If I had gone,the other man would have taken the picture. (I didn't go,so I took the picture and the other man didn't.)

If I'd had the money I would have given them some. (I didn't ,so I didn't give them any.)

If I had been born a hudred years ago,I would have had a different life.

Note

The if clause can appear in the second part of the sentence. No comma is used.

I wouldn't have come if I 'd known you were busy.