whats the diff btw beste and besta
If it is a female friend, you must say "min bästa vän" and if it is male friend you can say either "min bästa vän" or "min bäste vän". The special male form is used a lot in some parts of the country and very little in others.
Why doesn't "bäst" work here? I though "bästa" was plural?
It is, but it's also the definite, which is triggered by min.
I thought the final -e was only for words that can only be male (like "man" and "pojke"), but it seems to be for words that are male in a specific case too (like "professor" if it is a man). Right?
Yes, exactly - it depends on the person you're talking about, not the word, really.
Is there much difference in pronunciation? I'm assuming both endings are generally reduced to ə...
Yeah, I'd say it's generally faint but audible to a native. :)