The sign on the hotel window says:
Say again? It seems to me that when the window is closed, it is in use. It is keeping out the wind, and the rain, and the noise. When thw window is open, it isn't even a window, it's a hole. Holes have been around for hundreds of thousands of years, windows only since a week Tuesday. A hole is a necessary condition for a window. A window is not a necessary condition for a hole.
Mrs. Buce tries to be constructive. She suggests:
This is a noble effort, but I am not sure it makes the point. I suspect they want you to keep the window closed even when you are in the room, unless--well, unless you want to have the window open.
A more logical possibility would be:
But I don't think they mean to ask us to open the window. Anyway, if it open, it is not in use; they hardly need to say "please."
The same difficulties attend upon:
A friendlier, more nuanced approach might be:
We Strong Urge You to Use the Window
Except When You Are Not Using It
This seems to cover everything, but there may be a loophole. Mrs. Buce, on sober second thought, suggests a thoroughgoing and comprehensive approach:
Please Close or Open Window
When In Use or Not In Use
As the Case May Be