La meva mare vol seure en una butaca prop del passadís perquè li fa mal l'esquena.

In Catalan, possessives like meu / meva / teu / seva are usually used with a definite article:

• la meva mare = my mother
• el meu cotxe = my car

So unlike English, Catalan normally says the my mother literally, even though the real meaning is just my mother.

A common exception is direct address, for example:

• Mare, vine! = Mom, come here!

But in a normal statement, la meva mare is the standard form.

Vol is the 3rd person singular present form of voler, which means to want.

So:

• jo vull = I want
• tu vols = you want
• ell/ella vol = he/she wants

Here, la meva mare vol means my mother wants.

Seure means to sit or to sit down.

So:

• vol seure = wants to sit

In this sentence, it refers to taking a seat, not to making someone else sit. That is why seure is the right verb here.

Because after a conjugated verb like vol (wants), Catalan normally uses the infinitive of the next verb:

• vol seure = wants to sit
• vol menjar = wants to eat
• vol marxar = wants to leave

This works much like English: wants to sit.

Butaca can mean armchair, but in travel or theater contexts it often means a seat, especially a more comfortable individual seat.

So in this sentence, depending on context, una butaca could be understood as:

• an armchair
• a seat

If the meaning shown to the learner is something like seat near the aisle, that fits very well.

Here, en indicates the place where she wants to sit: in/on a seat.

So:

• seure en una butaca = to sit in/on a seat

Catalan often uses en with things like chairs, seats, or vehicles. In English, we choose between in and on depending on the object, but Catalan usage does not always match English exactly, so it is best to learn the whole expression:

• seure en una butaca

Prop de means near.

Then de + el contracts to del, so:

• prop de = near
• prop del passadís = near the aisle

And passadís means corridor or aisle, depending on context. In a plane, cinema, or theater, passadís is naturally aisle.

So:

• una butaca prop del passadís = a seat near the aisle

Because Catalan contracts de + el into del.

This is very common:

• de + el = del
• a + el = al

So:

• prop de el passadís → prop del passadís

This is just the normal grammatical form.

Because perquè means because.

Catalan distinguishes between:

• perquè = because
• per què = why / for what reason

So in this sentence:

• ... perquè li fa mal l'esquena = ... because her back hurts

The accent helps show that this is the conjunction because.

Literally, it works like this:

• li = to her
• fa mal = causes pain / hurts
• l'esquena = the back

So the structure is roughly:

• the back hurts to her
• more natural English: her back hurts

This is a very common Catalan pattern with body pain:

• Em fa mal el cap = My head hurts
• Li fan mal les cames = Her legs hurt
• Ens fa mal l'esquena = Our backs hurt / Our back hurts

The idea is not expressed the same way as in English, but it is very normal in Catalan.

With body parts, Catalan usually prefers:

• an indirect object pronoun to show whose body part it is
• plus the definite article with the body part

So instead of saying her back, Catalan often says essentially the back to her:

• li fa mal l'esquena

This is much more natural than:

• li fa mal la seva esquena (grammatically possible in some contexts, but not the normal choice here)

So for body parts, remember this pattern:

• em renta les mans = he washes my hands
• li fa mal el genoll = his/her knee hurts

Li is an indirect object pronoun meaning to him, to her, or to you (formal singular), depending on context.

In this sentence, it means to her, referring back to la meva mare.

So:

• li fa mal l'esquena = her back hurts
  literally, the back hurts to her

Because la becomes l' before a vowel sound.

So:

• la esquena → l'esquena

This is called elision, and it is very common in Catalan:

• la amiga → l'amiga
• el home → l'home
• la esquena → l'esquena

Esquena is feminine, which is why it takes la:

• la esquena → l'esquena

Many nouns ending in -a are feminine, and esquena follows that pattern.

So if you need to refer to it with an adjective, you would use the feminine form:

• l'esquena baixa
• l'esquena adolorida

It breaks down like this:

• La meva mare = my mother
• vol seure = wants to sit
• en una butaca = in/on a seat
• prop del passadís = near the aisle
• perquè = because
• li fa mal l'esquena = her back hurts

So the structure is:

subject + wants + infinitive + place + reason

That makes it a very natural everyday Catalan sentence.