Mi tía fue muy generosa y me dejó su coche para ir a la entrevista.

Because the sentence is talking about a completed event in the past.

• fue muy generosa presents her generosity as part of one specific occasion
• me dejó su coche is also one completed action

If you used the imperfect:

• era muy generosa = she was generally a generous person / that was her character
• me dejaba su coche = she used to let me use her car / she would let me use it repeatedly

So the preterite fits best for one particular act of generosity.

In Spanish, ser is normally used with qualities like generoso/a.

Here, fue muy generosa means something like she was very generous on that occasion. It does not necessarily mean this is her permanent personality; it just evaluates what she did in that moment.

Compare:

• Mi tía fue muy generosa = she was generous in that specific situation
• Mi tía era muy generosa = she was a generous person in general

So ser + generosa is completely natural here.

Here dejó means let someone use or lent.

The verb dejar has several meanings, including:

• to leave
• to let / allow
• to lend / leave something with someone for their use

In this sentence, me dejó su coche means she gave me the use of her car. In very natural English, that is often best understood as she lent me her car.

A very close alternative would be:

• me prestó su coche

That is a more direct way to say lent me her car, but me dejó su coche is also very natural in Spain.

Because me is an indirect object pronoun, meaning to me, and in Spanish these pronouns usually go before a conjugated verb.

So:

• me dejó su coche = she left/lent me her car

The full structure is basically:

• dejar algo a alguien = to leave/lend something to someone

So:

• dejó su coche a mí is not the normal neutral wording
• me dejó su coche is the normal form

You can add a mí only for emphasis:

• A mí me dejó su coche

Not 100% by grammar alone. Su can mean:

• his
• her
• your (formal singular)
• their

So Spanish often relies on context. In this sentence, the context makes it clear that su coche is most naturally understood as my aunt’s car.

If you wanted to remove all ambiguity, you could say:

• el coche de mi tía

Because this is Spanish from Spain.

In Spain, coche is the most common everyday word for car.

In other Spanish-speaking countries, people may say:

• carro
• auto
• automóvil

So coche is exactly what you would expect in Peninsular Spanish.

Because para + infinitive is used very often to express purpose.

Here:

• para ir a la entrevista = for going / in order to go to the interview

Spanish normally uses para + infinitive when there is no need to introduce a new subject explicitly.

A structure with para que + subjunctive is used when a different subject is involved or when the subject needs to be made explicit.

So:

• Me dejó su coche para ir a la entrevista = natural and concise
• Me dejó su coche para que fuera a la entrevista = possible in some contexts, but heavier and less natural here

Because al is only the contraction of a + el.

• a + el = al
• a + la = a la

So:

• al coche
• a la entrevista

There is no contraction with la.

Because tía is pronounced in two syllables:

• tí-a

The accented í shows that the i is stressed and does not combine with the a into a diphthong. This is a very common spelling pattern in Spanish with words like:

• tía
• día
• frío

So the accent helps show the correct pronunciation.

Because it refers to a specific interview, one that is already known from the situation.

Spanish often uses the definite article in cases where English might also say the:

• ir a la entrevista
• ir al trabajo
• volver a la oficina

If it were not a specific interview, you might say:

• ir a una entrevista

So la entrevista suggests a particular interview that was already planned.

Because Spanish usually omits subject pronouns when they are not needed.

The verb forms already tell you the person and number:

• fue = he/she was
• dejó = he/she left/lent

And the context tells you that the person is mi tía.

So Spanish normally says:

• Mi tía fue muy generosa y me dejó su coche...

rather than:

• Mi tía, ella fue muy generosa y ella me dejó su coche...

Adding ella would usually sound emphatic or contrastive, not neutral.

Yes. A very natural alternative is:

• Mi tía fue muy generosa y me prestó su coche para ir a la entrevista.

The difference is mainly this:

• me dejó su coche = very common, everyday way to say she let me use it / lent it to me
• me prestó su coche = more explicitly lent

Both are correct and natural. In Spain, me dejó el coche is especially common in everyday speech.