Answer:
2. If Tom doesn't work harder, he will not pass his exams.
3. If Jim and Kath buy a new car, they'll drive to Spain next week.
4. If we don't go to the supermarket, we won't have any food for supper.
5. If my sister reads your letter, she would be very upset.
Explanation: I hope I helped! If I didn't, please don't attack me! :(