Ack, so many posts, so many things to say...
Beli Orao wrote:Whence the Slavic tendency to say "in me X" for "I have X"? afaik this phenomenon occurs in all branches, being most obvious (to me) in Russian and documented but archaic/dialectal in South Slavic.
The phenomenon is generally considered to be a Uralic substrate interference, which was clearly more prominant the further north and east you go (hence how the "at me" construction has essentially displaced the inherited verb иметь in possessive constructions, with the exception of abstract possession). You see this same sort of construction all across the Uralic family.
Russian in particular has been heavily influenced by the Uralic languages, since for a long time there was quite a bit of contact between them. This is especially noticeable in the historical (and to a lesser extent modern) dialects of northwestern Russia, which are absolutely loaded with Finnic grammatical features; there may well have been a historical Sprachbund in this area encompassing Russian, the Baltic languages, and a number of Finnic languages.
A similar construction may well have existed in other Slavic languages, but it had relatively marginal use. That's one thing substratum effects are good at doing, however: taking a marginal construction and turning it into a much more productive pattern, based on a pattern in the substratum language.
Also, the preposition means "at" or "near", not "in". Your South Slavic language background is confusing you here; South Slavic "u" is a conflation of two Proto-Slavic prepositions, *vъ and *u, both of which are distinct in the northern Slavic branches.
Beli Orao wrote:(Also, is the genitive or accusative pronoun used? They look the same.)
It's the genitive. Just stick in a noun instead and it becomes obvious:
У меня машина.
"I have the car."
У сестры машина.
"My sister has the car"
Matt wrote:The genitive. They only appear the same for animate nouns. You'd say у моей машины, not у мою машину, for instance.
Well, they're distinct for singular first declension nouns that are animate as well (see above with сестра).
Zhen Lin wrote:This is found in other Indo-European languages. Latin and Greek, for example, have a possessive dative.
It's not quite the same thing. Proto-Slavic had a possessive dative as well (still productive in South Slavic, and with some relics in West Slavic, iirc). In East Slavic the possessive dative is mostly nonexistant.
Matt wrote:As far as I'm aware, it is. У моей машины есть две двери "my car has two doors", for example.
It is a possessive construction in this case, yes, though it isn't always.
schwatever wrote:This. I don't think I've seen У in Russian outside of as a prefix on certain verbs (mainly motion ones, where it's actually about direction away and possibly a homophone particle) and in possessive constructions:
Когде ты уйдёшь? - When will you leave?
У его нет машины. - He doesn't have a car.
Then you need to read a lot more Russian. The preposition "у" is quite commonly used outside of possessive constructions, where it has a number of different meanings. Its most common meanings are "at someone's house" (у Ивана "at Ivan's house", у нас "at our house") and "by" or "near" (у стены "by the wall", у окна "by the window"). It also means "pertaining to something" in a bit of a more abstract way, such as, uh... Что за логика у тебя? "What kind of logic is that [which you're using]?"
Also, both of those sentences needed correcting:
Когда ты уйдешь?
У
него нет машины.