Я положил чистую скатерть на стол, а мама поставила торт ближе к окну.

Russian often uses different put verbs depending on how the object is placed.

• положить = to lay / to put something down, usually thought of as lying flat
• поставить = to set / to place something standing or in position

So here:

• Я положил чистую скатерть на стол = I laid a clean tablecloth on the table
• мама поставила торт ближе к окну = Mom placed the cake closer to the window

A tablecloth is naturally imagined as something you lay down, so положить fits well.
A cake is often treated as something you set somewhere, so поставить sounds natural.

Russian is more specific than English here.

Because скатерть is the direct object of положил, so it must be in the accusative case.

• dictionary form: чистая скатерть
• in the sentence: чистую скатерть

The adjective changes because it agrees with the noun:

• скатерть = feminine singular
• accusative feminine singular of чистая = чистую

The noun скатерть itself does not change here, because it is inanimate, and for this noun type the accusative looks like the nominative.

So:

• nominative: чистая скатерть
• accusative: чистую скатерть

Good question. Скатерть is a feminine noun, but it belongs to a declension pattern where the accusative singular of an inanimate noun is the same as the nominative.

So:

• nominative: скатерть
• accusative: скатерть

That is why only the adjective clearly shows the accusative here:

• чистая скатерть → nominative
• чистую скатерть → accusative

This can feel strange to English speakers because English nouns usually do not show case clearly.

Because Russian uses different cases depending on whether you mean:

• movement to a place
• location in a place

With на:

• на стол = onto the table / to the table surface
  → accusative, because there is movement
• на столе = on the table
  → prepositional, because it describes location

Here the action is putting/laying the tablecloth onto the table, so Russian uses на стол.

Compare:

• Я положил скатерть на стол. = I put the tablecloth onto the table.
• Скатерть лежит на столе. = The tablecloth is lying on the table.

Because the preposition к takes the dative case.

• окно = window
• dative singular = окну

So:

• к окну = toward the window / to the window

In this sentence, ближе к окну means closer to the window.

This is a very common pattern:

• ближе к двери = closer to the door
• ближе к центру = closer to the center
• ближе к дому = closer to the house

That is just the normal Russian structure.

• ближе = closer / nearer
• к окну = to the window

Together: ближе к окну = closer to the window

Russian usually expresses this idea with ближе к + dative.

So if you want to say that something was moved to a position nearer another object, this pattern is very useful.

А often connects two clauses with a slight contrast or a shift of focus. It can mean something like:

• and
• while
• whereas
• sometimes a mild but

Here it separates two related actions by two different people:

• I laid the tablecloth on the table, and Mom placed the cake closer to the window.

Using а makes the second part feel like a natural switch to another person’s action.

Compare very roughly:

• и = simple addition
• а = addition with contrast, comparison, or change of subject
• но = stronger but

So а мама is very natural here because the speaker did one thing, and the mother did another.

In the Russian past tense, verbs agree in gender and number with the subject.

• Я положил = I put said by a male speaker
• Я положила = I put said by a female speaker

And:

• мама поставила = Mom placed
  because мама is grammatically feminine here

So the sentence tells us:

• the speaker is male, or is being presented with masculine agreement
• the mother is feminine, so поставила

This is one of the first things English speakers notice, because English past tense verbs do not change for gender.

Only the first verb would change:

• Я положил чистую скатерть на стол... = said by a man
• Я положила чистую скатерть на стол... = said by a woman

The rest would stay the same:

• ...а мама поставила торт ближе к окну.

Because торт is a masculine inanimate noun, and in the accusative singular, masculine inanimate nouns usually look the same as the nominative.

So:

• nominative: торт
• accusative: торт

That is why you get:

• поставила торт = placed the cake

If it were a masculine animate noun, the accusative would often look like the genitive instead.

Yes. Both are perfective past tense forms:

• положил ← положить
• поставила ← поставить

The perfective aspect shows the action as completed.

So the sentence presents finished actions:

• I laid the tablecloth
• Mom placed the cake

If you used imperfective verbs, the meaning would shift more toward process, repetition, or general action, depending on context.

For example:

• я клал / мама ставила would not fit as well in a simple finished narrative like this

So the perfective is very natural here.

No, Russian word order is fairly flexible because case endings show grammatical roles. But the original order is very natural and neutral:

• Я положил чистую скатерть на стол, а мама поставила торт ближе к окну.

This order gives a smooth narrative:

1. who did it
2. what they did
3. what object was affected
4. where it went

You can move things around for emphasis, but the tone changes. For example:

• Торт мама поставила ближе к окну.
  Emphasis on the cake
• Ближе к окну мама поставила торт.
  Emphasis on closer to the window

So the original sentence is probably the most standard version for a learner to imitate.

Because in Russian, descriptive adjectives usually come before the noun, just like in English:

• чистая скатерть = clean tablecloth
• вкусный торт = tasty cake

Putting the adjective after the noun is possible in some special styles or fixed expressions, but for ordinary speech the normal order is:

• adjective + noun

So чистую скатерть is the standard, natural word order.

Yes, often in context it would naturally mean my mom, even though Russian does not explicitly say моя мама here.

Russian often omits possessives when the relationship is obvious from context.

So depending on context:

• мама = Mom / my mom / mother

In this sentence, if the speaker is talking about their own home situation, English would very likely translate it as Mom or my mom.