I know that. But this does come up in conversation. I don't have a problem with saying I am taking a day off. I just don't know how to say it and not sound defensive.
What tone of voice to use?
Maybe I am not asking the right question.
That's why I am posting. Maybe somebody can even tell me what the question is.
I mean, to say "I love you," generally means it is said in a romantic, loving tone of voice and not screaming or like a robot.
Saying "I cleaned the kitchen" is just stating a fact and you don't have to be forceful or reticent or whatever when conveying factual information.
Saying, "I am really angry you did x, y, z" could be done in an irritated and angry voice, although it works better if one rephrases and is calm about it.
So, how does one say, I took the day off. If you work for someone else, you are permitted days off, you get vacation days and sick days, etc. When you work for yourself, what is the justification for taking a day off. I can't say that my boss gave me the day off. Or maybe I can? 
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The river is the melody
And sky is the refrain - Gordon Lightfoot