No puc venir aviat perquè vull esperar la meva germana.

Because Catalan usually makes a sentence negative by putting no directly before the conjugated verb.

• No puc = I can’t
• No vull = I don’t want
• No sé = I don’t know

So No puc venir aviat literally follows the same pattern as English I can’t come early/soon, but in Catalan the negative particle goes before the verb.

Puc means I can. It is the 1st person singular form of the verb poder = to be able to / can.

Catalan often leaves out subject pronouns when they are clear from the verb ending.

• puc = I can
• pots = you can
• pot = he/she/it can

So Catalan does not need jo here. You could say Jo no puc venir aviat, but jo is usually only added for emphasis or contrast.

After a modal verb like poder (can / be able to) or voler (want to), Catalan normally uses an infinitive.

So:

• puc venir = I can come
• vull esperar = I want to wait

This is very similar to English:

• can come
• want to wait

Here, venir is the infinitive to come.

It can mean either early or soon, depending on context.

In this sentence, venir aviat could be understood as:

• to come early
• to come soon

Both are possible translations of aviat. Catalan often uses the same word where English might choose one or the other depending on the situation.

Perquè means because here.

This is an important spelling distinction in Catalan:

• perquè = because
• per què = why / for what

So in this sentence:

• No puc venir aviat perquè vull esperar la meva germana.
• I can’t come early/soon because I want to wait for my sister.

The accent helps distinguish it from other similar-looking forms.

Vull means I want. It is the 1st person singular form of voler = to want.

Examples:

• Vull menjar. = I want to eat.
• Vull marxar. = I want to leave.
• Vull esperar. = I want to wait.

So perquè vull esperar... means because I want to wait...

Because Catalan esperar usually takes a direct object without a preposition.

So:

• esperar algú = to wait for someone
• esperar la meva germana = to wait for my sister

This is different from English, which needs for:

• English: wait for my sister
• Catalan: esperar la meva germana

This is a very common thing for English speakers to notice.

Catalan usually uses the definite article with possessives.

So:

• la meva germana = my sister
• el meu germà = my brother
• la seva casa = his/her house

That is normal Catalan structure. English does not use the here, but Catalan usually does.

There are some special cases where the article may be omitted, but for a learner, the safest rule is:

• use article + possessive + noun

So la meva germana is exactly what you would expect.

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

• el meu germà = my brother
• la meva germana = my sister

So:

• meu = masculine singular
• meva = feminine singular

This agreement is very common in Catalan.

Yes, a little. Catalan word order is somewhat flexible, although the original sentence is very natural.

The given order:

• No puc venir aviat perquè vull esperar la meva germana.

is perfectly standard.

You might also hear variations for emphasis, but learners should stick to the normal pattern:

• No
  • conjugated verb
• infinitive if needed
• adverb
• perquè
  • clause

So the original version is a very good model sentence.

Yes, vull often looks strange to English speakers.

It is roughly pronounced like bool or vool, depending on accent and region, but not exactly like an English word. The ll in Catalan can have different pronunciations depending on dialect.

For a beginner, the important thing is to recognize that:

• vull = I want
• it is the common 1st person singular form of voler

Even if pronunciation varies somewhat by dialect, the spelling and meaning stay the same.

Yes. Catalan, like English, often uses the present tense to talk about a present situation or a near-future plan.

• No puc venir aviat = I can’t come early/soon
• vull esperar la meva germana = I want to wait for my sister

The sentence describes the speaker’s current inability and intention, even if the actual coming happens later. That is completely normal in Catalan.