Translation:There is a man with a knife behind the curtain.
True, but the focus is placed on the fact that he has a knife, not the number of knives the man has. Or at least that it's a man with a knife. I don't know if it's an actual grammar rule or not, but I've heard it explained that in conversational Norwegian if you have that kind of possessive relationship, regardless of clearly stated possession, you can (and most Norwegians do) omit the indefinite article UNLESS you want to focus on the number of what they have. In this case knives.
There is a man with a knife - Det er en man med (en being optionally omitted) kniv
There is a man with one knife - Det er en man med én kniv
I'm assuming that it's somewhat due to the small difference in pronunciation between en and én and et and ett in spoken Norwegian making the differentiation confusing.
Another example is when asking someone if they have a car/phone/beard etc.
Har du bil/mobil/skjegg?
Dropping the article makes the focus on whether or not they have the object in question, not how many they have.
I hope that made some sort of sense. It made sense in my head... then I started typing. :D
Again, still wanting some more specific clarification from someone a little more... Norwegian. Than me...
If I were to wager a guess I'd say that it's partially because we need to let in all the light we can get during the winter months, and partially because we trust people to respect our privacy.
For me, it's because I know my cats would tear anything even vaguely resembling curtains to shreds within seconds.
Ohh.. Jeg liker virkelig så så mye Norge! Bare the more I learn the more I truly like Norwegian and, from these cultural insights, Norway as well!!!!!!! : ) For even wit so much curroption(in the degraded as whole sense and not only financially speaking), ego, pride, violence - just so much evil - THERE IS STILL GOODNESS and there are people who choose to be benign and be descent!
In Norwegian, there's more room for leaving out the indefinite article than there is in English.
We often do it when the number of the noun is irrelevant, like in this sentence where the presence of a knife is important, but not whether there's one or five.
It's also done when the focus is on the verb action, like with "å kjøre bil". The focus isn't on you driving a particular car, it's on you driving at all, or on your being able to drive.
When stating someone's profession, you also leave out the indefinite article: "Han er lege". However, if you're describing it further, not just stating it, you still need the indefinite article: "Han er en god lege".
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Missing audio is a technical issue, and unfortunately not something we contributors can fix.