1. It's cold. You should take a warmer jacket.
2. The students shouldn't forget to take their mobile phones in the exam.
3. George, you should try to do exercises every day.
4. You shouldn't eat so much junk food.
5. He shouldn't be so grumpy.
6. People should spend more time in cafes and restaurants.
7. You shouldn't speak to the doctor. He looks sick.
8. He should try to eat more, otherwise, he won't pass the exam.
9. Nancy, you should be more careful; otherwise, you won't pass the exam.
10. William shouldn't eat so much junk food.
I hope I helped you with this exercise, and good luck at school.