chuyển các câu sau sang If và Unless: Do your exercise or you will fail the exam?

chuyển cac câu sau sang If và Unless
1. do your exercise or you will fail the exam.
2. Save some money or you won't able to buy the house.
3. be have yourself or your parents will be very unhappy.
4. do it carefully or you will feel sorry afterwards
5. Ask him first or he won't offer to help.
6. be calm or you'll make a wrong desicion 
7. be careful or you'll cut yourself with that knife