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

1. You  have to  work hard if you want to become a doctor. It is not easy.

2. You  have to  come with me. I'm the only one who knows how to get there.

3. We  have to  do something to protect the environment.

4. You  don't have to  give me a lift. I will walk.

5. You  don't have to  do the washing up. Patty has done it already.

6. You don't have to go to the desert to see camels. You can see them at the zoo.