1. Keep silent or you’ll wake the baby up.
⇒If you don't keep silent, you will wake the baby up.
2. Stop talking or you won’t understand the lesson.
⇒If you don't stop talking, you won't understand the lesson
3. I don’t know her number, so I don’t ring her up.
⇒If I knew her number, I would ring her up
4. I don’t know the answer, so I can’t tell you.
⇒If I knew the answer, I would tell you
5. We got lost because we didn’t have a map.
⇒If we had had a map, we wouldn't have got lost
6. Susan felt sick because she ate four cream cakes.
⇒If Susan hadn't felt sick, she would have eaten four cream cakes
7. Without this treatment, the patient would have died.
⇒If it hadn't been for this treatment, the patient would have died
8. He lost his job because he was late every day.
⇒If he hadn't been late everyday, he wouldn't have lost his job.
9. Peter is fat because he eats so many chips.
⇒If Peter didn't eat so many chips, he wouldn't be fat
10. Robert got a bad cough because he started smoking cigarettes.
⇒If Robert hadn't started smoking cigarettes, he wouln't have got a bad cough