На витрине лежали кексы, рулеты и слойки.

Because на here means on / in the display case, and when на is used to describe location, it takes the prepositional case.

• витрина = display window / display case
• Prepositional singular: на витрине

So:

• на витрине = on the display / in the display case

In shop contexts, English often says in the display case, while Russian commonly says на витрине.

Витрина usually means a shop display window or display case. In this sentence, it most likely refers to the place where baked goods are displayed for customers.

So even though the literal translation may look like on the shop window, the natural meaning is more like:

• in the display case
• on display

Context matters a lot with this word.

Because the subject is plural:

• кексы, рулеты и слойки = cupcakes/cakes, rolls, and puff pastries

Since there are several items, Russian uses the plural past tense:

• лежал = he/it lay
• лежала = she/it lay
• лежало = it lay
• лежали = they lay

So лежали agrees with the plural subject.

Because the sentence is describing what was on display. Russian past tense often corresponds to English was/were in descriptions like this.

So the sentence is not literally focused on the action lay down, but rather on the state:

• На витрине лежали кексы...
  = There were cakes... on display = Cakes were lying on the display

Russian often uses verbs like лежать instead of a plain to be in this kind of scene-setting description.

This is a very common question. Russian often prefers a position/state verb where English might just use to be.

• были = were
• лежали = were lying / lay

Using лежали gives a more concrete picture: the pastries were lying there, arranged on the display.

Compare:

• На витрине были кексы... = There were cupcakes...
• На витрине лежали кексы... = The cupcakes were lying there on display.

Both can be understood, but лежали sounds more vivid and natural for baked goods placed flat on a surface.

Because they are the grammatical subject of the sentence.

The verb лежали answers the question what was lying there?

• кексы
• рулеты
• слойки

These are all nominative plural forms.

Singular → plural:

• кекс → кексы
• рулет → рулеты
• слойка → слойки

So the sentence structure is basically:

• On the display were lying [cakes, rolls, and puff pastries].

They are all plural nouns naming bakery items.

• кексы — from кекс; often translated as muffins, small cakes, or cupcakes, depending on context
• рулеты — from рулет; usually rolls, especially a Swiss roll / rolled cake
• слойки — from слойка; usually puff pastries

These words do not always match one exact English pastry term, because bakery vocabulary varies by country and culture.

Russian word order is flexible, and this order helps present the scene naturally.

Starting with На витрине sets the location first:

• На витрине лежали кексы...
  = On the display there were cakes...

This is a common Russian pattern when introducing what is somewhere.

If you changed the order:

• Кексы, рулеты и слойки лежали на витрине

that is also correct, but it puts more focus on the pastries themselves rather than on the display as the setting.

Usually no, not in this context.

Russian often distinguishes between objects that are:

• standing → стоять
• lying → лежать
• sitting → сидеть (for some objects/animals/people in certain positions)

Pastries like кексы, рулеты и слойки are normally thought of as lying on a tray or shelf, not standing. So лежали is the natural choice.

You might use стояли for things like:

• bottles
• cups
• jars
• vases

Yes, лежали comes from the imperfective verb лежать.

That matters because the sentence describes a state or situation, not a completed action. It is not about they lay down; it is about they were in a lying position / they were there.

So imperfective is exactly what you want here.

Russian commonly uses imperfective verbs for static descriptions like this.

A simple pronunciation guide is:

Na vee-TREE-nye lee-ZHA-lee KYEK-sy, roo-LYE-ty ee sloy-KEE.

A few stress points:

• витрИне
• лежАли
• кЕксы
• рулЕты
• слойкИ

The stressed syllable is important in Russian, because vowel quality changes in unstressed syllables.

Yes. This is one of those places where Russian and English package the idea differently.

Russian often says:

• на витрине = literally on the display / in the shop window

English often prefers:

• in the display case
• in the window
• on display

So when translating, it is better to choose the natural English phrase rather than translate на too literally every time.

Yes, it sounds natural, especially in a bakery or shop description.

It has a very normal descriptive feel:

• На витрине лежали кексы, рулеты и слойки.

A native speaker would easily understand it as a simple visual description of what was displayed for sale.