1.If she doesn’t work harder, she’ll lose her job. ----> She’ll lose her job unless she works hard
2.You can use my car, but have to keep it carefully.----> If you keep my car carefully, you can use it
3.If the work is finished by lunch, you can go home. ----> Unless the work isn't finished by lunch, you can go home
4.Keeping calm is the secret of passing your driving test. ----> If you keep calm, you can pass your driving test
5.You must work harder or you won’t pass the exam. ----> You won’t the exam unless you work harder
6. She must apologize to me or I’ll never speak to her again. ----> I’ll never speak to her again unless she apologizes to me
7. I didn’t have an umbrella with me and so I got wet. ----> I wouldn’t have got wet if i had had an umbrella
8. I’ll call the police if you don’t leave me alone. ----> Unless you leave me alone, i'll call the police
9. In the snowy weather, we don’t go to school. ----> If it snows, we don't go to school
10. Without Jack’s help, I wouldn’t have been able to move the table. ----> If it hadn't been for Jack's help, i wouldn't have been able to move the table