1. Open the window, will you?

2. Don't close the door, will you?
3. Open the window, won't you?
4. Have a cup of coffee, won't you?
5. Have a cup of coffee, will you?
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Ae they all grammatical?
Which ones are not okay?

1. OK

2. Don't close the door, please.
3. Would you please open the window.
4. OK
5. OK

1. "Open the window, will you?" - This is grammatically correct. It is a polite request or invitation using positive questioning, expecting the person to comply and open the window.

2. "Don't close the door, will you?" - This sentence is not grammatically correct. The use of both negative imperative ("don't") and positive questioning ("will you") creates a contradiction. It would be better to say "Please don't close the door, okay?"

3. "Open the window, won't you?" - This is grammatically correct. It is a polite request or invitation using negative questioning, expecting the person to comply and open the window.

4. "Have a cup of coffee, won't you?" - This sentence is grammatically correct. It is a polite invitation using negative questioning, expecting the person to accept the offer and have a cup of coffee.

5. "Have a cup of coffee, will you?" - This sentence is not grammatically correct. Similar to the second sentence, it combines both positive and negative linguistic elements creating a contradiction. A better way to say it would be "Would you like to have a cup of coffee?"