35) I
Fortunately, this is the very last case!
It is used for some very specific meanings, that’s why we've put off covering it for so long.
- It is used alone for a “tool” or an “agent” of an action. English mostly uses “with” or “by” instead: “молотком” (with hammer), ”ветром” (by wind), “силой” (by force)
- It is used alone with some verbs of “being”, “becoming”, “seeming”: Я стал учителем ~ “I have become a teacher”
It is also used with prepositions:
- с (со) = “with” (together with someone/something) — note that with prepositions “Я с ней” or even “Мы с ней” is the most natural way of saying “She and I”
- за/ перед — behind/ in front of
- над/ под — above/under
- между — between (also used with Genitive)
Мы с тобой
When you tell someone about "you and I" or "my friend and I" etc., it is most idiomatic to use мы с + your companion in Instrumental.
- Мы с тобой друзья. = You and I are friends.
- Мы с мамой вчера купили компьютер. = Mom and I bought a computer yesterday.
Of course, when translating sentences out of the blue, you cannot (strictly speaking) tell if a speaker means "I" or "we". This is rarely a source of confusion in real situations (where it is unlikely a speaker goes on randomly switching between "I" and "we" ).
Sometimes you can interpret a joint action using "and" or "with", whatever sounds more natural:
- Мы с ними вчера не говорили. = They and I didn't talk yesterday / I didn't talk with (to) them yesterday.
But wait, there's more!
Actually, Russian also has a handful of inconsistent cases that only exist for some words. They are (mostly) beyond the scope of this course:
- the Locative-2: the most important Why? Because it's obligatory with the nouns that it applies to. It expresses the meaning of place, with в,на or both. It exists for over a hundred masculine nouns: в году, на мосту, в лесу, на полу. And for about 20 feminine nouns in —ь: в крови (the ending is always stressed for both!)
- the Neo-vocative: a form of a name used when addressing a person. It exists for common names and several nouns: Вань! Вер! Алён! Мам! Пап! (just the last vowel sound is removed). The Historical vocative ("человек → человече") has been lost in modern Russian.
- the Genitive-2 for “some amount of substance”. Increasingly replaced by the usual Genitive but still can be used for several masculine nouns: “Хочу чаю”
- “Waiting” case: not much of a case, but actually the verb “ждать” (to wait) would use Accusative for people and things that can affect their appearance and Genitive for everything else (an event/thing that does not choose when to arrive).