1. "Can you open the window?"
  2. "Could she join us for lunch tomorrow?"
  3. "Should we start the presentation now?"
  4. "Might they consider our proposal?"
  5. "Must he leave so soon?"
  6. "Will you be able to solve the problem?"
  7. "Could you help me with this task?"
  8. "Should he apologize for his mistake?"
  9. "Can they finish the project by the deadline?"
  10. "Must we attend the meeting in person?"
  11. "Can't you stay a little longer?"
  12. "Couldn't she find a better solution?"
  13. "Shouldn't we check the results again?"
  14. "Mightn't they change their minds?"
  15. "Must he always be so critical?"
  16. "Can't you see the mistake here?"
  17. "Couldn't you have called earlier?"
  18. "Shouldn't he be more careful?"
  19. "Can't they make an exception?"
  20. "Must we always follow the same procedure?"