How to use "jak długo" ?

Hello,

I need more precisions on how to ask a question with "jak długo" depending on whether I ask "since when", "for how long" or "when in the future". In the question, should the expression "jak długo" be preceded by prepositions "na", "za" or left alone (with preposition being used only in the answer) ?

Thank you.

od kiedy or jak długo

Od kiedy mieszkasz w Polsce

Jak długo mieszkasz w Polsce


Na jak długo or Na ile

Na jak długo przyjechałeś do Polski

Na ile przyjechałeś do Polski


Kiedy or Za ile ( godzin, tygodni, miesiecy... - hours, weeks months...)

Kiedy będziesz w Polsce ( kiedy is for more general qs, you dont know if its matter of days, weeks or months so the answer could be also more general - Za pare tygodni ( in a couple of weeks))

Za ile (dni...) będziesz w Polsce ( za ile you use when you know that smth is a matter of hours, days, months ... but you dont know precise time - the answer is usualyalso more precise - Będe w Polsce za 5 dni ( I'll be in Poland in 5 days))

I'm not a good teacher and I dont know if my answers are helpful but maybe you'll understand a bit from this explanations :)

For example, jak długo jesteś w polsce? How long have you been in Poland? Teaching point for Poles learning English. This should not be translated as, 'how long are you in Poland?, as this means sth completely different. It means that you are in Poland, perhaps on a work exchange program or for a temporary stay, and you plan to return to your home country. Oh, I'm in Poland for a week, then I return to Scotland for example.

Za jak długo nie bedzie means in a short time it/there will not be....(doesn't sound so right, tho)

Na jak długo zostajesz? How long are you staying (for)?

Like is so often the case, what is grammatically correct and what sounds good are two very different things.