Su hermana pequeña prefiere el tobogán, pero también quiere probar el columpio.

Su can mean his, her, your (formal), or even their, depending on context.

So Su hermana pequeña could mean:

• his little sister
• her little sister
• your little sister (formal usted)
• their little sister

Spanish often leaves this kind of thing to context. If you need to make it clearer, Spanish can add extra words, for example:

• la hermana pequeña de él = his little sister
• la hermana pequeña de ella = her little sister

In Spanish, adjectives usually come after the noun, so:

• hermana pequeña = little/younger sister

That is the most natural order here.

If you put the adjective before the noun, it can sometimes sound more literary, emotional, or change the nuance. For example:

• su pequeña hermana can sound more affectionate, like his/her dear little sister

But in normal everyday Spanish, su hermana pequeña is the usual way to say his/her little sister or younger sister.

It can mean either, depending on context.

In many cases, hermana pequeña is used the same way English uses little sister, meaning younger sister, not necessarily physically small.

But it can also literally mean she is a small child. Context tells you which meaning is intended.

So this phrase can suggest:

• she is the speaker’s younger sister
• and/or she is a young child

Because the subject is su hermana pequeña, and the verbs have to be conjugated to match she.

The infinitives are:

• preferir = to prefer
• querer = to want

But with ella / she, they become:

• prefiere = she prefers
• quiere = she wants

These are both irregular stem-changing verbs:

• preferir: e → ie
• querer: e → ie

So:

• ella prefiere
• ella quiere

Because after a conjugated verb like quiere (wants), Spanish often uses a second verb in the infinitive.

So:

• quiere probar = wants to try

This is very common in Spanish:

• quiere comer = wants to eat
• prefiere descansar = prefers to rest
• puede venir = can come

Only the first verb is conjugated here; the second stays in the infinitive.

Spanish often uses the definite article where English does not, especially when talking about things in a general or familiar context.

So:

• prefiere el tobogán literally looks like prefers the slide
• quiere probar el columpio literally looks like wants to try the swing

In natural English, you might just say she prefers the slide if a specific playground is being discussed, or sometimes simply she prefers slides in a more general sentence. Spanish is more comfortable using el/la here.

In this sentence, el tobogán and el columpio most likely refer to the playground equipment in that situation.

In Spain:

• tobogán = slide
• columpio = swing

These are the normal playground meanings.

A useful note:

• columpio can refer to a single swing, but in context it can also be understood more generally as the swings or the swing set area, depending on the situation.

Yes, también can move around a bit, but its position affects what it sounds like it is emphasizing.

In the sentence:

• pero también quiere probar el columpio

también means also / too, and here it naturally connects with the second idea: she prefers one thing, but she also wants to try another.

This position is very natural.

You may also hear:

• pero quiere también probar el columpio
• pero quiere probar también el columpio

These are possible, but the original sentence is the most neutral and natural.

Because pero is the normal word for but when you are adding a contrasting idea, not correcting a negative statement.

Here we have:

• She prefers the slide, but she also wants to try the swing.

That is simple contrast, so pero is correct.

Sino is used after a negative statement to correct it:

• No quiere el tobogán, sino el columpio.
• She doesn’t want the slide, but rather the swing.

So in your sentence, pero is the right choice.

Because the personal a is normally used before specific people (and sometimes pets), not things.

Compare:

• quiere probar el columpio = she wants to try the swing
• quiere ver a su hermana = she wants to see her sister

Since el columpio is a thing, there is no personal a.

In Spanish, a comma is commonly used before pero when it connects two full clauses, especially in clear written style.

Here the two parts are:

• Su hermana pequeña prefiere el tobogán
• pero también quiere probar el columpio

Since both sides contain a verb and form complete ideas, the comma is natural and standard.

Yes. Spanish often omits subject pronouns and even other repeated subjects when the verb ending makes the subject clear.

For example, if the context is already obvious, you could say:

• Prefiere el tobogán, pero también quiere probar el columpio.

That still clearly means She prefers the slide, but she also wants to try the swing.

In your sentence, Su hermana pequeña is included for clarity or emphasis.

A simple Spain Spanish guide:

• prefiere ≈ preh-FYE-reh
• quiere ≈ KYE-reh
• tobogán ≈ toh-boh-GAN
• columpio ≈ koh-LOOM-pyo

A few helpful notes:

• qu before i/e sounds like k
• ie in quiere and prefiere is like ye
• the written accent in tobogán shows the stress is on the last syllable: -gán