Ответ:
1. If you don’t sleep enough, you get tired.
2. Whenever it rains, I take my umbrella.
3. If it is sunny tomorrow, we will go to the park.
4. If I have a party, I will invite all my friends.
5. If you cook dinner, I’ll wash the dishes.
6. If my brother is in trouble, I will help him, of course.
7. You won’t understand the rule if you don’t listen to the teacher.
8. If it snows, the children will play snowballs.
9. You will never finish your work if you waste your time like that.
10. If he is not very busy, he will agree to go to the museum with us,
11. If he reads fifty pages every day, his vocabulary will increase greatly.
12. If it rains tomorrow, our game will be cancelled.
13. If it doesn’t rain, their plants die.
14. If you run, you will catch the bus.
15. She will come if you invite her.
16. If we study hard, we will pass our exams.
17. When you heat ice, it melts.