Work in pairs. Complete the sentences with your own ideas.

For the world to be a peaceful place, ... 

1. we should ...

2. we shouldn’t ... 

3. we must ... 

4. we mustn’t ... 

5.  we don’t have to ... 

To be in a good mood every day, ... 

6. you should ... 

7. you shouldn’t ... 

8. you have to ... 

9. you don’t have to ...