Mijn
mijn (van mij) is used when you want to present that person or things are my/mine.
Mijn naam is David. - My name is David.
Mijn zoon heet David. - My son is David.
Je (jouw)
Je or jouw is used when you want to present that person or things are your/yours (informal).
Waar woont je zus?
Wat is jouw telefoonnummer?
Uw
uw is used when you want to present that person or things are your (polite or formal used).
Mag ik weten uw naam, alstublieft ? - May I know your name, please.
Mag ik uw paspoort te controleren? - May I check your passport?
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