Mi vecina se apuntó al festival el año pasado y este año quiere apuntarse otra vez con nosotras.

Because apuntarse is the full verb here. It is a pronominal verb, meaning it normally comes with a pronoun like me, te, se, nos.

• se apuntó = she signed up / joined
• quiere apuntarse = she wants to sign up / join

The difference is just grammatical context:

• In a normal conjugated verb, the pronoun goes before the verb: se apuntó
• After another verb + infinitive, the pronoun can attach to the infinitive: quiere apuntarse

So both forms come from the same verb: apuntarse a algo.

Not literally reflexive in the English sense of herself. Here, se is part of the verb apuntarse, which in Spain very commonly means to sign up, to join in, or to put your name down for something.

So:

• apuntar usually means things like to point, to note down, or to aim
• apuntarse means to sign oneself up / join

In many cases, you should learn apuntarse as a whole unit rather than trying to translate se word by word.

Yes. Both are correct.

With a conjugated verb plus an infinitive, Spanish often allows the pronoun in two places:

• quiere apuntarse
• se quiere apuntar

Both mean the same thing. In this sentence, quiere apuntarse sounds very natural.

Because a + el contracts to al in Spanish.

So:

• a el festival → al festival

This happens almost always with a + el.

A similar contraction is:

• de + el → del

But note: this only happens with el, not with la.

• a la fiesta stays a la fiesta

Because Spanish often uses time expressions without a preposition where English might use in, last, or this.

So:

• el año pasado = last year
• este año = this year

This is very common:

• el lunes = on Monday
• la semana pasada = last week
• este verano = this summer

You do not normally say en el año pasado for last year.

Because it refers to a completed action in the past: she signed up last year.

The preterite se apuntó presents the action as a finished event.

• Mi vecina se apuntó el año pasado = she signed up last year

If you used the imperfect, it would suggest something ongoing, habitual, or backgrounded, which does not fit as well here.

The accent mark shows that this is the third person singular preterite form:

• yo apunté
• tú apuntaste
• él/ella se apuntó

The accent helps distinguish the stress pattern and also distinguishes forms in writing.

So apuntó means he/she signed up, not the infinitive or another tense.

Because the sentence is talking about a current desire or intention:

• este año quiere apuntarse otra vez = this year she wants to sign up again

So the timeline is:

• last year: completed past action → se apuntó
• this year: present intention/desire → quiere apuntarse

That shift in tense is perfectly normal.

Otra vez means again.

Yes, de nuevo would also work here:

• quiere apuntarse otra vez
• quiere apuntarse de nuevo

Both are correct. Otra vez is very common and natural in everyday speech.

Sometimes otra vez can also mean one more time or even yet again, depending on context, but here it simply means again.

Because nosotras is the feminine plural form of we/us.

So con nosotras means with us, referring to a group of females. This suggests that the speaker is female and the group is all female.

• con nosotras = with us (all female)
• con nosotros = with us (mixed group or all male)

This is a very common question for English speakers, since English does not mark this difference.

Yes. Vecina is feminine, so it means female neighbour.

• mi vecino = my male neighbour
• mi vecina = my female neighbour

The possessive mi does not change, but the noun does.

Yes, very much so. In Spain, apuntarse a is extremely common for things like:

• joining an activity
• signing up for a class
• putting your name down for an event
• deciding to come along

Examples:

• Me apunto al curso. = I’m signing up for the course.
• ¿Te apuntas? = Are you in? / Do you want to join?

A more formal alternative is inscribirse, but apuntarse is very natural in everyday Spanish in Spain.

It most naturally means that she wants to sign up with us, that is, together with the speaker’s group.

So the idea is not just she wants to sign up again, but she wants to do it again together with us.

Depending on context, that could mean:

• joining the same team or group
• registering alongside the others
• taking part together

So con nosotras adds the idea of company or shared participation.