Употребите подходящий по смыслу модальный глагол:
1. What (can/should) I do for you?
2. Where (may/should) I turn to get to the Metro station?
3. You (mustn’t/shouldn’t) cross the street on the red light.
4. Peter (can/must) watch TV from morning till night.
5. We (may/must) take care of our parents.