Ответ:

1.you must/you can

2.you cant/you must

3.you cant/you must

4.you cant/you must

5.you cant/you must

6.you cant/you must

Ответ:

1. you must be careful here; you can fall here
2. You mustn't litter here; you must throw the rubbish into the bin
3. You mustn't bring pets; you must pay a fine if you bring a pet
4. You mustn't make fire in the forest; you can save the forest
5. You mustn't talk loudly in the library; you must work quietly in the library
6. You mustn't use your mobile phone; you must turn of your mobile phone