the "u" + acc (gen?) pronoun construction

[Beli Orao]

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.

(Also, is the genitive or accusative pronoun used? They look the same.)

[Matt]

(Also, is the genitive or accusative pronoun used? They look the same.)

The genitive. They only appear the same for animate nouns. You'd say у моей машины, not у мою машину, for instance.

[Zhen Lin]

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.

This is found in other Indo-European languages. Latin and Greek, for example, have a possessive dative.

[Niedokonany]

I suspect it's a Uralic substrate influence that it has gained so much ground in Russian, displacing иметь. Finnish also employs a 'circumlocution' of this kind. Which doesn't mean it can't have existed as an option in Common Slavic.

[Beli Orao]

The genitive. They only appear the same for animate nouns. You'd say у моей машины, not у мою машину, for instance.

Is your example a possessive construction, though? Unless the South Slavic equivalent "у мојој машини, у моју машину" means something completely different.

[Matt]

The genitive. They only appear the same for animate nouns. You'd say у моей машины, not у мою машину, for instance.

Is your example a possessive construction, though? Unless the South Slavic equivalent "у мојој машини, у моју машину" means something completely different.

As far as I'm aware, it is. У моей машины есть две двери "my car has two doors", for example.

[Miekko]

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.

(Also, is the genitive or accusative pronoun used? They look the same.)

"U" doesn't mean "in" in East Slavic, and in South Slavic that's just one of its many optional meanings.
U X.gen isn't exclusively used with pronouns, it's used with nouns.

Similar constructions are more common a way of constructing such statements than a dedicated verb (such as "have"), cross-linguistically speaking.

[schwhatever]

"U" doesn't mean "in" in East Slavic

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.

Latin and Greek, for example, have a possessive dative.

Arguably, Russian does too, but only idiomatically still. The only place I've encountered it is with ages:

Сколько тебе лет?
how.many//how.much 2P.SING.DAT summer(s)?
How old are you? (ie: How many summers do you have?)

[Matt]

Сколько тебе лет?
how.many//how.much 2P.SING.DAT summer(s)?
How old are you? (ie: How many summers do you have?)

Ha, I've never made the connection between лет (for someone's age) and лето 'summer' until now.

[Mecislau]

Ack, so many posts, so many things to say...

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.

(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"

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).

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.

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.

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.