Learn Hardcore Russian: Сегодня вечером у нас репетиция в большом зале. - This evening we have a rehearsal in the big hall.

It isn’t redundant; it just specifies which evening: tonight, not yesterday evening or tomorrow evening. Structurally, сегодня means today, and вечером (literally in the evening) tells you the time of day. Together they are similar to English this evening / tonight.

What exactly does у нас mean, and how does it mean “we have”?

Literally, у нас means by us / at our place / with us.

Russian usually expresses “to have” with a structure у + [person in genitive] + [thing], for example:

у меня книга – I have a book (literally: by me [there is] a book)
у нас репетиция – we have a rehearsal
у них экзамен – they have an exam

So у нас is the standard way to say we have in many contexts, especially for scheduled events, possessions, or things happening “on our side”.

Why is there no separate word for “have” in this sentence? Where is the verb?

Russian often omits the verb “to be” in the present tense in sentences like this.

Full underlying structure: Сегодня вечером у нас (есть) репетиция.
Natural spoken/written Russian: Сегодня вечером у нас репетиция.

The verb есть (there is / there are / to have) is usually dropped in simple present statements of existence or possession. The meaning “we have a rehearsal” is understood from the у нас + noun structure and the context of time (сегодня вечером).

Can I say мы имеем репетицию to mean “we have a rehearsal”?

Normally, no. That sounds unnatural or overly formal/technical.

The verb иметь (“to have”) is used:

in some formal or legal styles
in fixed expressions (e.g. иметь право – to have the right)

For everyday possession or scheduled events (classes, rehearsals, meetings), Russian uses у нас / у меня / у него + noun. So you should say у нас репетиция, not мы имеем репетицию.

Why is репетиция in the nominative case? I expected some object form.

In the structure у нас репетиция, the noun репетиция is actually the grammatical subject of the sentence, even though in English we think “we have a rehearsal”.

You can think of the Russian logic as:

У нас репетиция. – A rehearsal is (there) at us.
- у нас – an adverbial phrase showing “at whose place / on whose side”
- репетиция – thing that exists (subject, nominative)

So репетиция stays in the nominative singular, just like the subject of a simple sentence.

What case is вечером, and why does it look like that?

Вечером is the instrumental case of вечер (evening).

A small group of time-of-day words commonly use the instrumental to say “in the [part of the day]”:

утром – in the morning
днём – in the daytime
вечером – in the evening
ночью – at night

You could think of it as a fixed adverbial form meaning “(during) the evening”, so you just learn вечером = in the evening as a standard pattern.

Why do we say в большом зале, not в большой зал?

Because here we are talking about location (where?), not direction (where to?).

Russian uses в + prepositional case for “in/at” a place (static location), and в + accusative case for “into” a place (movement):

в большом зале – in the big hall (prepositional: где? where?)
в большой зал – (into) the big hall (accusative: куда? where to?)

In your sentence, we’re not describing movement into the hall; we are simply saying that the rehearsal takes place in the big hall, so в большом зале is correct.

How do большом and зале agree with each other grammatically?

Зал is a masculine noun. In the prepositional singular, it becomes в зале.

The adjective большой must match the noun in gender, number, and case:

masculine, singular, prepositional → большом

So:

nominative: большой зал – a big hall
prepositional: в большом зале – in the big hall

The matching endings -ом (for the adjective) and -е (for the noun) show that they go together and are in the prepositional case.

What is the difference between Сегодня вечером у нас репетиция and Сегодня вечером у нас будет репетиция?

Both can refer to the future (tonight), but the nuance is a bit different:

Сегодня вечером у нас репетиция.
– Very natural, especially for fixed or scheduled events. It sounds like a simple statement of your timetable: tonight, we have rehearsal.
Сегодня вечером у нас будет репетиция.
– Adds a slightly stronger feeling of future occurrence or maybe of a special / one-time event. It can sound a bit more emphatic: “there will be a rehearsal tonight”.

In everyday speech about regular schedules (lessons, rehearsals, meetings), the version without будет is extremely common.

Why are there no words like “a” or “the” (articles) in репетиция and зал? How do I know if it’s “a rehearsal” or “the rehearsal”?

Russian simply does not have articles (no “a”, “an”, “the”). The ideas of “a” vs “the” are expressed by:

context and what is already known
word order and stress
sometimes demonstratives like этот / тот (“this / that”) if you need to be explicit

In this sentence, English could translate it as “a rehearsal” or “the rehearsal” depending on context. Russian Сегодня вечером у нас репетиция в большом зале is neutral; a common translation would be “We have rehearsal in the big hall tonight.”

Can I change the word order, for example to У нас сегодня вечером репетиция в большом зале? Does it change the meaning?

Yes, you can change the word order; the basic meaning stays the same.

Some natural variants:

Сегодня вечером у нас репетиция в большом зале. (original)
У нас сегодня вечером репетиция в большом зале.
Сегодня вечером репетиция у нас в большом зале.

Russian word order is fairly flexible. The changes mostly affect focus and emphasis:

Starting with Сегодня вечером highlights the time.
Starting with У нас highlights who has the rehearsal (as opposed to someone else).

All of these would be understood the same way in normal conversation, with only slight differences in what you’re emphasizing.

Is вечером a noun or an adverb here?

Historically it’s the instrumental form of the noun вечер, but in usage here it works almost like an adverb of time.

You don’t treat it like a full noun phrase (you don’t say an article, you don’t add an adjective in the same case, etc.); you just use it as a fixed time expression meaning “in the evening”. So grammatically it’s an instrumental noun form, functionally it’s an adverbial time expression.