Ma sœur ramasse un coquillage blanc et le garde dans sa poche.

Because sœur is a feminine singular noun, and French possessive adjectives agree with the noun they go with:

• ma = my + feminine singular noun
• mon = my + masculine singular noun
• mes = my + plural noun

So:

• ma sœur
• mon frère
• mes sœurs

One important detail: in some cases, French uses mon before a feminine noun that starts with a vowel sound, but that does not apply here because sœur does not start with a vowel sound.

They are both in the present indicative.

More specifically:

• ramasse = 3rd person singular of ramasser
• garde = 3rd person singular of garder

The subject is Ma sœur, so French uses the il/elle/on form of the verb.

This present tense can describe:

• something happening now
• a habitual action
• a vivid action in a story

So French present works a lot like English present, though exact usage depends on context.

Not exactly. Ramasser usually means something like:

• to pick up
• to gather
• to collect

In this sentence, it suggests that the shell is lying somewhere and the sister picks it up.

So ramasser is more specific than a general verb like prendre (to take). It gives the idea of lifting something from the ground, beach, or another surface.

This is a very common French pattern.

• un coquillage introduces the object for the first time
• le refers back to that same object afterward

So the sentence first says a white shell, then instead of repeating the full noun, French uses the direct object pronoun le:

• un coquillage blanc
• le garde

Here le means it, referring to coquillage.

Because coquillage is masculine singular, the pronoun is le.

Because in a normal statement, French object pronouns usually come before the conjugated verb.

So:

• elle le garde = she keeps it
• not elle garde le

This is one of the biggest differences from English word order.

A useful pattern to remember is:

• subject + object pronoun + verb

For example:

• Je le vois = I see it
• Nous la prenons = We take it
• Ma sœur le garde = My sister keeps it

The pronoun comes after the verb mainly in affirmative commands:

• Garde-le ! = Keep it!

But that is not what is happening here.

Because in French, most adjectives come after the noun.

So:

• un coquillage blanc
• une maison blanche
• un livre intéressant

Color adjectives, including blanc, usually come after the noun.

English often puts adjectives before the noun, but French usually does the opposite.

There are some common adjectives that often come before the noun, such as those about beauty, age, goodness, and size, but blanc is not one of them.

In this sentence, sa agrees with poche, not with the owner.

That is a very important French rule: possessive adjectives agree with the thing possessed, not the person who possesses it.

Since poche is feminine singular, French uses:

• sa poche

This would stay the same even if the owner were male:

• Son frère garde le coquillage dans sa poche.

Here sa poche still means his pocket, because poche is feminine.

So:

• son livre because livre is masculine
• sa poche because poche is feminine

Because the two verbs share the same subject: Ma sœur.

French, like English, can connect two actions with et and keep the same subject without repeating it:

• Ma sœur ramasse un coquillage blanc et le garde dans sa poche.

This works like:

• My sister picks up a white shell and keeps it in her pocket.

You could repeat the subject in some contexts, but it would usually sound unnecessary here.

So the structure is:

• subject + verb 1 + object + et
  • verb 2 + rest

with the same subject understood for both verbs.

Because dans is the normal French preposition for in / inside when something is physically inside something else.

So:

• dans sa poche = in her pocket

This is the most natural choice for something being placed or kept inside a pocket, bag, box, room, etc.

Examples:

• dans un sac = in a bag
• dans la boîte = in the box
• dans sa main would be different, because that means in her hand

So dans is exactly the expected preposition here.

Usually, noun gender in French has to be learned along with the noun itself.

So it is best to learn:

• un coquillage
• not just coquillage

There are some patterns that sometimes help, but they are not completely reliable. For most learners, the safest strategy is to memorize the article with the noun from the start.

That is why the later pronoun is le:

• un coquillage
• le garde

Both show that coquillage is masculine singular.

The spelling œ is a ligature in French. In modern learning, the main thing to know is that sœur is simply the standard spelling of the word.

For pronunciation, sœur sounds roughly like sur in British English fur, though not exactly. The final r is the French r, and the vowel is a French sound that English does not match perfectly.

So for a learner, the key points are:

• sœur is one word
• œ is normal French spelling here
• you should learn its pronunciation as a whole word rather than trying to sound out each letter separately