Third Conditional: If + Past Perfect; Second Clause + would + have + past participle
eg:
1) If you had studied more, you would have passed the exam.
2) I would have been happier if I had made the right choice.
3) If they had written more, they would have become best selling writers.
4) If Sarah had left earlier, she would have arrived at 3 o'clock.
5) I wouldn't have let you get in if I had known you were not allowed.
6) They would not have forgiven you if I had not told them so.
7) If you hadn't learnt Chinese, you wouldn't have moved to China.
8) If people had been more polite, the world would have been a better place.
9) If Charlie had eaten all the cake, his parents would have gone and buy another one.
10) If I had knocked on the door, she would have answered.
Sper ca te-am ajutat!
