Прилавок у входа.

Because the preposition у normally requires the genitive case when it means by / near / at.

• dictionary form: вход
• genitive singular: входа

So:

• у входа = by the entrance / near the entrance

This is a very common pattern in Russian:

• у двери = by the door
• у окна = by the window
• у дома = by the house

Here у means by, near, or at in the sense of location.

It does not mean possession here. Russian у can also appear in sentences like у меня есть... meaning I have..., but in Прилавок у входа, it is purely locational:

• у входа = near the entrance

So a learner should think of у + genitive here as a common way to say that something is positioned close to something else.

Yes, from an English point of view, it can feel like a verb is missing.

Russian often omits is / are in the present tense. So Прилавок у входа can be understood like:

• Прилавок находится у входа
• Прилавок есть у входа would not be natural here, but English learners often expect something like is

The natural full version is:

• Прилавок находится у входа = The counter is located by the entrance

In short, Russian often leaves out the present-tense is.

It can function as either, depending on context.

• As a label, caption, or sign-like expression, it can be just a noun phrase: Counter by the entrance
• In normal speech, it can also work as a short complete statement, with the verb understood: The counter is by the entrance

Russian uses these short verbless present-tense expressions much more freely than English does.

Прилавок usually means a counter, especially in a shop or market setting.

It can refer to:

• a sales counter
• a shop counter
• a display counter

It is a masculine noun.

Basic form:

• прилавок

A learner should note that it is not the most general word for every kind of table or desk. It is specifically associated with a place where goods are sold or displayed.

Because Russian has no articles.

English distinguishes:

• a counter
• the counter

Russian does not mark that difference with separate words. So прилавок can mean:

• a counter
• the counter

The exact meaning depends on context.

Yes. Russian word order is flexible.

You could also say:

• У входа прилавок

Both versions are understandable, but the emphasis changes a little.

• Прилавок у входа starts with the thing being talked about: the counter
• У входа прилавок starts with the location: by the entrance

In many contexts, the original order sounds very natural, especially if the topic is the counter itself.

Because it is the main noun of the phrase/sentence.

In Прилавок у входа:

• прилавок is the thing being identified or located
• у входа is the location phrase

So:

• прилавок stays in the nominative
• входа changes to genitive because of у

This is a useful pattern to notice:

• main thing = often nominative
• location after certain prepositions = another case, here genitive

Yes. Russian has several ways to express near the entrance.

For example:

• у входа
• возле входа
• около входа

They are all possible, but у входа is very common and compact.

Roughly speaking:

• у входа = right by the entrance / at the entrance
• возле входа = near the entrance
• около входа = around/near the entrance

The differences are small in many everyday situations.

It is pronounced approximately like this:

• прила́вок у вхо́да

Stress:

• прила́вок
• вхо́да

A rough English-style approximation:

• pree-LAH-vuk oo VKHO-duh

That approximation is only rough, but the main thing to remember is the stress on:

• -ла́- in прилавок
• вхо́- in входа

Yes, very easily.

Because Russian has no articles, Прилавок у входа could refer to:

• a counter near the entrance
• the counter near the entrance

Context tells you which one is meant.

For example:

• on a map or sign, it may just label a location
• in conversation, it may refer to a known specific counter

So learners should not try to force a single article meaning onto the Russian phrase without context.