Natural speed would be much appreciated.
Number 1. Can you shut the curtains please? Can you shut the curtains please? Can you shut the curtains please?
Number 2. Can you open the windows please? Can you open the windows please? Can you open the windows please?
Number 3. Can you erase the whiteboard? Can you erase the whiteboard? Can you erase the whiteboard?
Number 4. Can you shut the door please? Can you shut the door please? Can you shut the door please?
Number 5. Can you switch on the light please? Can you switch on the light please? Can you switch on the light please?
Number 6. Can you switch off the light please? Can you switch off the light please? Can you switch off the light please?
Number 7. Can you speak up please? Can you speak up please? Can you speak up please?
Number 8. Can you repeat please? Can you repeat please? Can you repeat please?
Note: This is vernacular. While grammatically correct, it is considered more polite to say, "Would you please..." instead of "Can you..."