Mentrestant, la meva filla talla una patata i després la bull amb aigua.

In Catalan, possessives are very often used together with the definite article, so la meva filla is the normal way to say my daughter.

A few useful points:

• la = the
• meva = my (feminine singular)
• filla = daughter

So literally it looks like the my daughter, but that is just normal Catalan grammar.

You will often see this pattern:

• el meu germà = my brother
• la meva mare = my mother
• els meus amics = my friends
• les meves germanes = my sisters

Catalan can sometimes omit the article in certain contexts, but for a learner, article + possessive + noun is the safest normal pattern.

Because filla is a feminine singular noun, and the possessive has to agree with it.

The forms of my are:

• el meu = masculine singular
• la meva = feminine singular
• els meus = masculine plural
• les meves = feminine plural

Since filla is feminine singular, you need la meva filla.

Compare:

• el meu fill = my son
• la meva filla = my daughter

Mentrestant means meanwhile or in the meantime.

In this sentence, it works as an adverb introducing the whole action:

• Mentrestant, la meva filla talla una patata...
• Meanwhile, my daughter cuts a potato...

It is very common at the beginning of a sentence, often followed by a comma, especially when it sets the scene for what happens next.

You may also see it in slightly different positions depending on style, but sentence-initial position is very natural.

Talla is the 3rd person singular present tense of the verb tallar, which means to cut.

So:

• jo tallo = I cut
• tu talles = you cut
• ell / ella talla = he / she cuts

In the sentence, the subject is la meva filla, so the verb must be talla:

• la meva filla talla = my daughter cuts

Una patata means a potato.

Here is the breakdown:

• una = a / an (feminine singular)
• patata = potato

Since patata is feminine in Catalan, it takes the feminine article una.

Compare:

• un llibre = a book
• una patata = a potato

Even though English potato does not have grammatical gender, Catalan nouns do, so the article has to match.

Here després means afterwards, then, or later.

So:

• i després la bull = and then she boils it

By itself, després usually means afterwards / then.

If you want to say after something, Catalan often uses:

• després de = after

For example:

• després de dinar = after lunch

But in your sentence, després is being used on its own as an adverb meaning then.

Here la is a direct object pronoun meaning it, and it refers back to una patata.

So the sequence is:

• talla una patata = she cuts a potato
• després la bull = then she boils it

Because patata is feminine singular, the pronoun is la.

This is very common in Catalan: once the object has been mentioned, it can be replaced by a pronoun.

Examples:

• Veig la casa → La veig
  I see the house → I see it

• Compra una poma → La compra
  She buys an apple → She buys it

In Catalan, object pronouns usually come before a conjugated verb.

So:

• la bull = she boils it
• literally: it boils

This is normal Catalan word order for weak pronouns.

Compare:

• La veu = she sees her/it
• El compra = he buys it
• Les talla = she cuts them

This is different from English, where the object pronoun usually comes after the verb:

• English: she boils it
• Catalan: la bull

A useful rule for learners:

• with a normal finite verb, pronouns usually go before it
• with an infinitive or some imperatives, they often attach after it

Yes. Bull is the 3rd person singular present of bullir, which means to boil.

So:

• jo bullo = I boil / I am boiling
• tu bulls = you boil
• ell / ella bull = he / she boils

In your sentence:

• la bull = she boils it

This verb can describe either something boiling on its own or someone boiling something, depending on context. Here, because there is a direct object pronoun la, it clearly means to boil it.

Yes, amb aigua literally means with water.

In context, it means that the potato is boiled using water, and in natural English you might often say in water instead.

Catalan and English do not always choose the same preposition in these everyday expressions. So amb aigua is perfectly natural Catalan here.

Useful comparison:

• bullir alguna cosa amb aigua = boil something with water
• natural English often: boil something in water

So you should understand it as the normal Catalan way to express the cooking method, not necessarily as a word-for-word match to English.

The comma is there because Mentrestant is an introductory adverb setting the time frame for the whole sentence.

So the structure is:

• Mentrestant, = Meanwhile,
• la meva filla talla una patata... = my daughter cuts a potato...

This kind of comma is very common and helps readability. You will often see the same thing with words like:

• Després, ... = Afterwards, ...
• Avui, ... = Today, ...
• Finalment, ... = Finally, ...

In informal writing, punctuation can vary a bit, but the comma here is standard and natural.