1.i think i must to help my frieds with his homework  this week 

2I think I mustn't go to the night club this week

3i think i coudn't go to the cinema this week

1. I must wash up this week. I must dust the furniture this week.

2. I mustn't go to gym this week. I mustn't walk with my dog this week.

3. I shouldn't go to cafe this week. I shouldn't go to the doctor this week.