Wasn't part of the point of this lesson to teach us that "nem van" becomes "nincs"? So why isn't it "A busz nincs ott"?
It isn't the verb which is being negated (we aren't declaring the nonexistence of a bus), it's the location. The bus exists; where? not there, but here.
Hungarian syntax is a lot like Perl syntax. There's more than one way to do it, but most of the ways you try to do it at first won't work.
I wouldn't know; I've mostly done Python, Lua for mods, and a half-hearted attempt at Java. (I gave up because it's so strongly typed) Perl just looks like obfuscated anything and everything to me. And, I think most of the ways you try to do anything won't work at first in every language, not just Perl. ;)
What about the earlier sentence "Nem, a radio nincs itt.; Are we talking about the nonexistence of the radio, or just the nonexistence of the radio here. This makes my head spin.
Yes, what about that sentence? It might be "Nem, a rádió nem itt van"? What would be the difference?
"A rádió nincs itt." -- I look at this place and see that the radio isn't here -> "rádió" is negated. ("the nonexistence of the radio here")
"A rádió nem itt van." -- This is not the place where the radio is -> "itt" is negated.
Barbara, remember that 'nem' can mean 'no' as well as 'not'. In your sentence, it means 'no' and stands alone, so to speak -- it is not negating anything in the clause that follows.