Ответ:
1. You will be tired if you don't sleep.
2. It will not be possible if they support us.
3. If you help me, I will give you a lot of money.
4. She will not be slim if she doesn't stop eating so much chocolate.
5. If we sing some carols, they will be happy.
6. Robert will read the whole essay if he likes it.
7. He will not get a better job if he doesn't pass that exam.
8. If you don't exercise and eat healthy, you will put on weight.
9. They will buy some popcorn it they go to the cinema.
10. If he go to the gym, he will get quite muscular.
11. If we don't protect the white dolphins, they will become extinct.
Объяснение:
Тут в каждом предложении будущее время (The Future Tense), по правилу после if мы обязательно должны за месть будущего времени использовать самое обычное(The Present Simple Tense). Вот и всё.