3 Fill in the sentences with have to, don't have to.

1 You have to go to the desert to see camels. You can see them at the zoo.
2 You have to work hard if you want to become a doctor. It is not easy.
3 You don't have to come with me. I'm the only one who knows how to get there.
4 We have to do something to protect the environment.
5 You don't have to give me a lift. I will walk.
6 You have to do the washing up. Patty has done it already.