1. If only you sister could come as well.
2. It looked as if the house had been occupied for several months.
3. He was too tired to watch the end of the film.
4. I was the last person to hear about the accident.
5. It's very important to keep the environment clean.
6. If he had been informed, he would have attended the seminar simply.
7. In spite of being short of money, I'll lend you some.
8. I warned boys not to swim out too far.
9. If she hadn't forgotten to add salt, the food wouldn't have been tasteless.
10. If only you had told me earlier.