Present Perfect. Change the sentences to negative.

1. She has been sick lately.

2. He has exercised this week.

3. I have called her today.

4. We have worked on this together.

5. They have missed their chance.

6. I have tried to reach him.

7. She has put on a black dress.

8. He has failed to get their attention.

9. It has been easy.

10. We have known each other for a long time.