If you don't like the present, you can always return it.If they had had the money, they would have gone on vacation.He would write to me if he had my new address.You don't regret it if you follow your heart.Would you have apologized to him if you knew he was upset?I would have met her last night if I had arrived earlier.If he had recognized me, he would have said hello.Unless you leave on time, you will miss the train.