Mi hermana prefiere una cuenta de ahorros.

Preferir is the infinitive, meaning to prefer. In this sentence, the verb has to be conjugated because the subject is mi hermana (my sister).

The verb preferir changes like this in the present tense:

• yo prefiero
• tú prefieres
• él/ella/usted prefiere
• nosotros preferimos
• ustedes prefieren
• ellos/ellas prefieren

Since mi hermana = she, the correct form is prefiere.

Also, preferir is a stem-changing verb: e → ie in most present-tense forms, so prefer- becomes prefier-.

No. Prefiere can mean:

• he prefers
• she prefers
• you prefer (formal singular, usted)

In this sentence, because the subject is mi hermana, we know it means she prefers.

Because mi is the correct possessive adjective used before a noun:

• mi hermana = my sister
• mi casa = my house

Mía is a possessive pronoun or stressed possessive form, and it is not used directly before the noun in this way.

Compare:

• mi hermana = my sister
• la hermana mía = my sister (less neutral / more emphatic / less common in many contexts)

So in a basic sentence, mi hermana is the normal choice.

In Spanish, mi does not change for gender. It stays the same with masculine and feminine singular nouns:

• mi hermano = my brother
• mi hermana = my sister

It only changes for number:

• mi hermana = my sister
• mis hermanas = my sisters

So mi agrees in number, not gender.

Because mi as a possessive adjective (my) does not take an accent mark.

Compare:

• mi = my
• mí = me / myself after a preposition

Examples:

• Mi hermana = My sister
• Para mí = For me

So in this sentence, mi has no accent because it means my.

Because cuenta is a feminine singular noun, so it takes the feminine singular indefinite article una.

• una cuenta
• not un cuenta

You can often tell the noun is feminine because it ends in -a, though that is not always true for every noun in Spanish.

Literally, it means something like account of savings.

This is a very common Spanish structure:

• noun + de + noun

Here:

• cuenta = account
• de ahorros = for savings / of savings

Together, cuenta de ahorros is the standard way to say savings account.

Because Spanish and English do not always package ideas the same way.

In Spanish, ahorros (savings) often appears in the plural in this banking expression:

• cuenta de ahorros

Even though English uses savings too, learners sometimes expect a more word-for-word pattern and wonder why it is not something else like cuenta de ahorro everywhere.

In much of Latin America, cuenta de ahorros is a standard and very natural term.

Sometimes yes, depending on the country or institution. Banking vocabulary can vary by region. However, cuenta de ahorros is very common and natural in Latin America.

So for a learner, cuenta de ahorros is a good phrase to know and use.

Because possessive adjectives like mi, tu, su, nuestro, etc. normally replace the article.

So Spanish says:

• mi hermana
• not la mi hermana

This is similar to English, where we say my sister, not the my sister.

No. This is normal Spanish word order:

• Mi hermana = subject
• prefiere = verb
• una cuenta de ahorros = object

So it follows the common pattern:

Subject + Verb + Object

That makes it a very straightforward sentence.

Usually, the present tense here suggests a general preference:

• Mi hermana prefiere una cuenta de ahorros.
  = My sister prefers a savings account.

It sounds like a general opinion or usual preference, not necessarily something happening at this exact moment.

Context could make it more specific, but on its own, it most naturally sounds general.

Yes, cuenta is a word with several meanings in Spanish, depending on context. It can mean:

• account
• bill/check (at a restaurant)
• a form of the verb contar in some contexts (he/she counts), though not here

In this sentence, because of de ahorros, it clearly means account, specifically a bank account.

So una cuenta de ahorros can only really be understood here as a savings account.

You would change the words that need to agree in number:

• Mi hermana prefiere una cuenta de ahorros.
• Mis hermanas prefieren unas cuentas de ahorros.

Changes:

• mi → mis
• hermana → hermanas
• prefiere → prefieren
• una → unas
• cuenta → cuentas

Notice that de ahorros stays the same.

Normally, no. In standard Spanish, you would usually need an article or possessive with hermana in this kind of sentence.

Natural options would be:

• Mi hermana prefiere una cuenta de ahorros.
• La hermana prefiere una cuenta de ahorros. if a specific sister has already been identified in context

By itself, Hermana prefiere... does not sound natural in standard usage.