Show me the Modal Verb

In each of the following sentences there's a modal verb. Try to find it!

1. You have to be careful.

2. My grandmother may win the gold medal in Kung-Fu .

3. Most dogs can bark fluently.

4. Give me a call in case you should travel abroad.

5. You ought to revise your lessons regularly.

6. You needn't justify yourself; I do understand the situation!

7. Could you possibly hand me that blue file over here, please?

8. Law must be respected.

9. You cannot park your car here.

10. You 'd better do the next quiz.