1. You would know English better if you tried to study harder.

2. I should have left Moscow yesterday if you hadn't sold me tickets to Samara. 

3. If I were you, I would never told him to do so.

4. If  I had known that it was going to rain, I would have stayed at home.

5. I shall go for a walk, if I'm staying.

6. I should lend you my textbook if you solved it.

7. If we had bought the tickets, you would have payed for us.

8. If they were here, the wouldn't let me go.

9. We should be glad if he found a job.

10. If he were younger, he would be th youngest champion.