La decoración de la sala es muy bonita.

Because decoración is a feminine noun in Spanish, so it takes the feminine article la.

A useful pattern is that many nouns ending in -ción are feminine:

• la decoración
• la canción
• la conversación
• la información

So when you learn a noun like decoración, it is best to learn it together with its article: la decoración.

De la sala means of the living room or in the living room, depending on how naturally you would say it in English.

In this sentence, de links decoración with sala:

• la decoración de la sala = the decoration/decor of the living room

Spanish often uses de where English uses of:

• la puerta de la casa = the door of the house
• el color del coche = the color of the car

So here, de la sala tells you which decoration you are talking about.

Because in Spanish, when talking about a specific noun like sala, you usually include the article.

So:

• de la sala = of the living room
• not usually de sala

Spanish uses articles more often than English does. Even when English says living room without the, Spanish often prefers la sala.

Here, sala usually means living room or sitting room.

In many Latin American contexts, la sala is the main room where people sit, talk, or receive guests.

Depending on region and context, Spanish can also use:

• la sala = living room
• el salón = living room / hall / large room
• la sala de estar = living room

In this sentence, la sala is most naturally understood as the living room.

Because bonita here describes a more general, inherent quality of the decoration, so Spanish uses ser:

• La decoración de la sala es muy bonita.

Use ser for things like:

• identity
• characteristics
• descriptions
• what something is like in general

Use estar more for:

• location
• condition
• temporary states
• how something is at the moment

Compare:

• La decoración es muy bonita. = The decor is very pretty.
• La sala está muy bonita. = The living room looks very pretty right now.

That second sentence with estar is also possible, but it changes the focus a little. It sounds more like the room looks nice at the moment.

Because bonita agrees with la decoración, which is feminine singular.

In Spanish, adjectives usually agree in gender and number with the noun they describe:

• la decoración bonita → feminine singular
• el cuarto bonito → masculine singular
• las decoraciones bonitas → feminine plural
• los cuartos bonitos → masculine plural

So:

• la decoración → feminine
• therefore bonita

Muy means very.

So:

• bonita = pretty / beautiful / nice
• muy bonita = very pretty / very beautiful

It comes before the adjective:

• muy bonito
• muy interesante
• muy grande

This is similar to English word order with very.

In this sentence, bonita comes after es because it is part of the predicate:

• La decoración de la sala = subject
• es muy bonita = what is being said about the subject

So the structure is:

• Subject + ser + adjective

This is very common in Spanish:

• La casa es grande.
• El libro es interesante.
• La comida es buena.

You can also put an adjective directly after a noun, as in:

• la decoración bonita

But that is a different structure. Here the sentence is saying The decor is very pretty, so the adjective comes after es.

Yes. Bonito/a can mean pretty, beautiful, or nice, depending on context.

For example:

• Una casa bonita = a pretty/nice house
• Qué bonito = how nice / how pretty
• La decoración es bonita = the decor is pretty / nice

In this sentence, very pretty or very nice are both natural interpretations.

Often, yes. Decoración can mean:

• decoration
• decor
• sometimes the style or arrangement of decorative elements

So la decoración de la sala could be understood as:

• the decoration of the living room
• the living room decor

In everyday English, decor may sound more natural than decoration in some contexts, but the Spanish word decoración covers both ideas.

Yes, but it does not mean exactly the same thing.

• La decoración de la sala es muy bonita.
  = The living room decor is very pretty.

• La sala es muy bonita.
  = The living room is very pretty.

The first sentence talks specifically about the decor.
The second talks about the room as a whole.

So both are correct, but they focus on different things.

It is pronounced approximately like:

deh-koh-rah-SYON

A few pronunciation notes:

• The stress is on the last syllable: -ción
• The c in ción is pronounced like s in Latin America
• The written accent mark in decoración shows where the stress goes

So the strongest part is:

• deco-ra-CIÓN

Because the two la words belong to two different nouns:

• la decoración = the decoration/decor
• la sala = the living room

Each noun needs its own article. This is very normal in Spanish.

So the sentence is literally structured like:

• The decoration of the living room is very pretty.

That is why you see la ... de la ...

Yes, in some contexts that translation works well.

Strictly speaking, de la sala most directly means of the living room, but English often prefers a more natural rendering such as:

• The living room decor is very pretty.
• The decoration in the living room is very pretty.

Which translation sounds best depends on context. The Spanish sentence itself points to the decor associated with the room.

It is neutral and natural. It works in both everyday conversation and more careful speech.

Nothing in the sentence is especially slangy, formal, or literary. It is just a standard descriptive sentence:

• La decoración de la sala es muy bonita.

So it is a good model for everyday Spanish.

The basic pattern is:

article + noun + de + article + noun + ser + adverb + adjective

In this sentence:

• La = article
• decoración = noun
• de = of
• la = article
• sala = noun
• es = is
• muy = very
• bonita = pretty / nice

So the full structure is:

La decoración de la sala es muy bonita.
= The decor of the living room is very pretty.

This is a very useful pattern you can reuse:

• La comida del restaurante es muy buena.
• El color de la pared es muy bonito.
• La música de la película es muy interesante.