Ma sœur préfère une robe rose, mais ma mère choisit un sac marron.

Because ma means my. French uses possessive adjectives like English does:

• ma sœur = my sister
• ma mère = my mother

If you said la sœur or la mère, that would mean the sister or the mother, which is less personal and does not show whose sister or mother you mean.

Ma is the feminine singular possessive adjective meaning my. It is used before a feminine singular noun.

Both nouns are feminine:

• une sœur
• une mère

So:

• ma sœur
• ma mère

Compare:

• mon frère = my brother
• ma sœur = my sister

Because French nouns have grammatical gender.

• robe is feminine, so it takes une
• sac is masculine, so it takes un

This does not mean the object itself is biologically feminine or masculine. It is just part of how French grammar works, and you usually have to learn the gender with each noun.

The accents are part of the correct spelling and also help show pronunciation.

The infinitive is préférer = to prefer.
In the sentence, préfère is the he/she/it or I form in the present tense:

• je préfère = I prefer
• il/elle préfère = he/she prefers

The verb préférer changes its accent in some forms. This is a common pattern in French spelling-changing verbs.

Because the subject changes, and each verb is conjugated to match its subject.

• ma sœur préfère = my sister prefers
• ma mère choisit = my mother chooses

Both subjects are third-person singular, so the verbs are in the elle form:

• elle préfère
• elle choisit

The verbs are different because they mean different things:

• préférer = to prefer
• choisir = to choose

In French, adjectives often come after the noun. Colors usually do.

So:

• une robe rose = a pink dress
• un sac marron = a brown bag

This is different from English, where adjectives usually come before the noun:

• a pink dress
• a brown bag

Yes. Rose is an adjective here, and it agrees with the noun it describes.

Since robe is feminine singular, the adjective is also feminine singular. In this case, rose already has the same form for masculine and feminine singular, so you do not see a spelling change:

• un pull rose
• une robe rose

But in the plural, you would add -s:

• des robes roses

So agreement still exists, even if the singular form looks the same.

This is a very common learner question. Color words in French usually agree, but some color words that originally come from objects are often treated as invariable, meaning they do not change form.

Marron originally means chestnut, and as a color adjective it is usually invariable:

• un sac marron
• une veste marron
• des sacs marron

So even if the noun is feminine or plural, marron often stays marron.

Mais means but. It connects two contrasting ideas:

• Ma sœur préfère une robe rose
• mais ma mère choisit un sac marron

So the sentence is showing a contrast between what the sister prefers and what the mother chooses.

Sœur can be tricky for English speakers because of the vowel sound.

A rough guide is:

• sœur sounds somewhat like sir or fur in some English accents, but with rounded lips

Important points:

• the œu sound is a classic French vowel sound
• the final r is the French r, not a strong English r

If you are just starting, it is enough to recognize that sœur is pronounced as one syllable.

No, the final -t in choisit is normally silent.

So choisit sounds roughly like shwa-zi.

This is common in French: many final consonants are not pronounced unless there is a liaison, and there is no liaison here.

Yes, but that would change the meaning.

• ma sœur = my sister
• sa sœur = his sister or her sister
• ma mère = my mother
• sa mère = his mother or her mother

So the possessive adjective must match the meaning you want. In this sentence, ma shows that the speaker is talking about my sister and my mother.