Ex. 12. She has hurt her thumb.3. They have done their homework.4. They have gone home.5. We have had our breakfast.6. Our relatives have come to see us.7. I have written a letter to my pen-friend.8. My mother has taken my brother to the...Ex. 22. I haven't done my homework.3. We haven't had dinner.4. My parents haven't come back from work.5. I haven't seen my friend today.6. My elder sister hasn't put Fanta in the fridge.7. I haven't written a letter to my pen-friend this month.8. The doctor says my brother hasn't broken his ankle.