I know that 'one' is the general word in this context, but sometimes 'man' is also correct. I think this is one such case: ' A man cannot own another man.' Probably not PC, but still. It is certainly better than the suggested sentence starting with a number '1'...
The suggested version with 1 is because of how Duolingo makes numbers accepted if you write them with numbers instead of letters (their algorithm for that isn't quite perfect…)
The reason A man cannot own another man isn't accepted is that there are at least two closer Swedish translations for that, En människa kan inte äga en annan människa or the same with en man or with en person. So while the idea may be the same, it's not really a translation in terms of this language course. In real life, translations can be a lot more free, but here we want the translations to be as exact as possible.
äga is a verb meaning '(to) own'.
ege is not a Swedish word. Maybe you're thinking about the adjective egen/eget/egna which means 'own' as in 'my own book'.
Should it not be får in this case? Since it is still physically possible even though it is illegal
You could make the same argument for the English source sentence, though. If it had said "may", we'd have used får as the default translation.
Ah ok :) So is colloquial Swedish just as interchangeable with can/may as colloquial English is, where nobody except an English teacher would pull you up?
Depends on the sentence and its subject, I suppose. I think using "can" here is essentially a euphemism in both languages.
The sentence audio is something like manniFa, and the word audio is something like manniSHa.