В багетной мастерской есть постеры.

Because в means in here, and when в shows a static location, Russian normally uses the prepositional case.

• dictionary form: мастерская
• after в for location: в мастерской

So в багетной мастерской means in the frame workshop / framing workshop.

A useful contrast:

• в мастерской = in the workshop
• в мастерскую = into the workshop (motion toward it)

So the case changes depending on whether you mean location or movement.

Because багетной is an adjective modifying мастерской, and in Russian adjectives must agree with the nouns they describe.

Here:

• мастерская is feminine singular
• after в with location, it becomes мастерской in the prepositional case
• the adjective must match it, so багетная becomes багетной

So:

• багетная мастерская = a framing workshop
• в багетной мастерской = in a framing workshop

Both words change together.

Not here. This is a very important vocabulary point.

In Russian, багет can mean a frame moulding or decorative strip, not just a French loaf. So:

• багетная мастерская is usually a framing workshop or picture-framing shop
• it is a place where people make or sell frames, matting, and similar items

So this sentence is not about a bakery.

Here есть means there is / there are in an existential sense.

So the structure is:

• В багетной мастерской есть постеры.
• literally: In the framing workshop, there are posters.

Russian often omits есть when talking about possession in the present tense, especially in sentences like:

• У меня есть книга. = I have a book.

But in sentences introducing the existence of something somewhere, есть is also very common and natural.

Here it tells us that posters are present / available there.

Because постеры is the nominative plural form of постер.

• singular: постер
• plural: постеры

In existential sentences with есть, the thing that exists is often in the nominative:

• Есть постер. = There is a poster.
• Есть постеры. = There are posters.

So постеры is simply the normal plural form here.

It is in the nominative plural.

That may feel a little surprising to an English speaker, because English does not show this kind of case marking. In this sentence:

• в багетной мастерской = location phrase
• есть = there is/are
• постеры = the things that exist there

So постеры functions like the grammatical subject of an existential sentence, and it appears in the nominative plural.

Sometimes Russian can omit есть, but doing so changes the feel of the sentence.

Compare:

• В багетной мастерской есть постеры.
  = There are posters in the framing workshop.
  This clearly presents their existence/availability.

• В багетной мастерской постеры.
  This sounds less neutral and more context-dependent. It may feel incomplete, contrastive, or stylistically unusual without special context.

So for a straightforward statement like this, есть is the natural choice.

No, Russian word order is fairly flexible, but changing it changes the emphasis.

Neutral order here:

• В багетной мастерской есть постеры.

This sounds like:

• setting the location first
• then saying what is there

Other possible orders:

• Постеры есть в багетной мастерской.
  More emphasis on posters.

• Есть постеры в багетной мастерской.
  Possible, but less neutral by itself.

So the original version is a very natural, neutral way to say it.

Because Russian often puts the setting or location first, especially in existential sentences.

This pattern is very common:

• Где? — location first
• Что там есть? — what exists there

So the sentence naturally answers the idea:

• What is there in the framing workshop?
• There are posters.

Starting with the location makes the sentence sound organized and natural in Russian.

It is a borrowed word. Russian has taken постер from English poster.

Its forms behave like a regular masculine noun in Russian:

• постер = poster
• постеры = posters

So even though the word is borrowed, its grammar is fully Russian.

Yes, but the nuance can be a little different.

• плакаты often means posters in a broad sense, especially printed posters, notices, or wall posters
• постеры often feels a bit more modern, commercial, or decorative, especially for art prints or stylish wall posters

In a framing-shop context, постеры sounds very natural, because it can suggest decorative prints intended for framing.

No. В can take different cases depending on meaning.

With location: usually prepositional

• в мастерской = in the workshop

With motion toward a place: usually accusative

• в мастерскую = into the workshop

So the case after в depends on whether you mean where something is or where something is going.

You would use the singular:

• В багетной мастерской есть постер.

Compare:

• есть постер = there is a poster
• есть постеры = there are posters

So only the noun changes from singular to plural.

It is more like an indefinite existential statement.

Russian does not have articles like a and the, so it does not mark definiteness the same way English does. In this sentence, постеры is understood as something like:

• there are posters
• there are some posters

not usually:

• the posters are in the framing workshop

If Russian wanted to talk about specific posters already known from context, it would usually use different word order or a different sentence structure.

The pattern is:

[location] + есть + [thing that exists]

So here:

• В багетной мастерской = location
• есть = there is/there are
• постеры = thing(s) that exist there

This is one of the most useful Russian sentence patterns for beginners and intermediate learners. Similar examples:

• В комнате есть стол. = There is a table in the room.
• В магазине есть книги. = There are books in the store.
• На стене есть картина. = There is a painting on the wall.