Воткните am, is, are в последующих предложениях:1. I not three years

Воткните am, is, are в последующих предложениях:
1. I not three years old.
2. This suitcase very heavy.
3. The dog asleep.
4. They students.
5. I .. hot. Open the window, please
6. Ann at home but her children at school.
7. The exam not difficult.
Помогите решить пожалуйста