There are two distinctive words for ‘our’ as well as ‘my’ in Korean. They are spelled different and, therefore, sound different. However, one of them is used in a situation where it looks it should’ve been replaced by the other. I myself am Korean and I have never realized for the first thirty years of my life until I was asked recently. I was asked because I happen to be in a business where language matter is of paramount interest. (I work as a professional in a Korean translation company) In other words, most Koreans who have not been asked will never notice even though it so obvious once they are. Amazing how familiarity can blind you.
In Korean, ‘my book’ or ‘my friend’ is translated as it is. Word meant for ‘my’(내) is used in this case. If you put those phrases in any machine translator, it will surely give back to you the original, ‘my book’ and ‘my friend.’
However, it’s different for ‘my country’ and ‘my father.’ Word meant for ‘our’(우리) is used. If you put those Korean phrases in a crappy machine translator, it might give you ‘our country’ or ‘our father.’ Why? I did spend some time to figure this out myself. What makes those two cases different? I know I have used them all my life and never made a mistake in using the wrong determiner for two different cases. However, I never questioned what seems now very odd. I wasn’t able to answer myself and had to look up, and aha! It made sense!