Mi abuelo empezó a roncar en el sofá mientras veíamos la película.

Because empezó is the preterite, and here it describes a completed event that happened at a specific moment in the past: your grandfather started snoring.

In contrast, veíamos is imperfect because it describes the background action already in progress: we were watching the film.

This is a very common contrast in Spanish:

• preterite = the event that happens / begins / interrupts
• imperfect = the ongoing background situation

So the sentence sets up this idea:

• while we were watching the film → ongoing background
• my grandfather started snoring → one event that happened during it

Because empezar is commonly followed by a + infinitive when it means to begin/start doing something.

So:

• empezó a roncar = he started to snore
• empezó a hablar = he started to speak
• empezó a llover = it started to rain

This is just the normal pattern in Spanish:

• empezar a + infinitive

You cannot usually leave out the a here.

Roncar means to snore.

So:

• Mi abuelo empezó a roncar = My grandfather started snoring

Related forms:

• ronco = I snore
• roncaba = he/she was snoring, used to snore
• roncó = he/she snored

It is a regular -ar verb.

Because veíamos is the imperfect, which shows an action that was in progress in the past: we were watching.

If you said mientras vimos la película, it would sound unnatural in this context, because mientras here introduces a background action happening over a stretch of time.

So:

• mientras veíamos la película = while we were watching the film

The imperfect works well with while, when, and other background-time expressions when something else happens during that ongoing action.

Mientras means while.

It links two actions happening at the same time:

• Mi abuelo empezó a roncar
• mientras veíamos la película

So the idea is that one event happened during another ongoing activity.

It is very common to use mientras with the imperfect when describing background actions:

• Mientras estudiaba, sonó el teléfono.
• Mientras caminábamos, empezó a llover.

Yes, you often can, but there is a slight difference.

In many contexts:

• ver una película = to watch a film
• mirar una película = to look at/watch a film

Both are possible, and both are understood.

Very generally:

• ver often focuses more on seeing/perceiving
• mirar often focuses more on looking/watching intentionally

But with TV and films, Spanish speakers often use ver very naturally, so veíamos la película sounds completely normal.

Because en el sofá is the normal way to say on the sofa in Spanish.

Spanish often uses en where English uses in, on, or at, depending on context.

So:

• en el sofá = on the sofa
• en la mesa can mean on the table
• en la cama = in/on the bed, depending on context

Sobre literally means on top of / over, and it usually sounds more physical, literal, or formal. For ordinary location with furniture, en is the usual choice.

The word is written sofá because the stress falls on the last syllable: so-FÁ.

In Spanish, words ending in a vowel, n, or s normally have stress on the second-to-last syllable unless there is a written accent. Since sofá is stressed on the last syllable, it needs the accent mark.

The accent mark tells you how to pronounce it correctly.

The accent in veíamos helps show the correct stress and keeps the verb form clear.

It comes from ver in the imperfect:

• yo veía
• tú veías
• él/ella veía
• nosotros veíamos
• vosotros veíais
• ellos veían

The accent also helps show that the i and a are pronounced in separate syllables.

So veíamos is pronounced roughly as ve-Í-a-mos, not as one merged vowel sound.

Because Spanish often uses possessive adjectives like mi, tu, su just as English does:

• mi abuelo = my grandfather

You could sometimes omit it if the context is already very clear, but mi abuelo is the most natural and complete way to say it here.

Also, unlike English, Spanish often uses the definite article with body parts and personal belongings, but with family relationships, the possessive is very common:

• mi madre
• mi hermano
• mi abuelo

No. Abuelo just means grandfather.

If you need to specify, you can say:

• abuelo materno = maternal grandfather
• abuelo paterno = paternal grandfather

But normally, mi abuelo is enough unless the distinction matters.

Yes. Spanish word order is flexible, although the original sentence is very natural.

You could also say:

• Mientras veíamos la película, mi abuelo empezó a roncar en el sofá.

This puts the time/background part first.

Both versions are correct. The difference is mostly about emphasis and flow:

• Mi abuelo empezó... first = focus first on what happened
• Mientras veíamos... first = set the scene first

Yes, but it changes the meaning.

• empezó a roncar = he started snoring
• estaba roncando = he was snoring

The original sentence focuses on the moment the snoring began.

If you say Mi abuelo estaba roncando en el sofá mientras veíamos la película, then you are describing snoring as an ongoing background action, not the start of it.

So both are correct, but they express different things.

Because película is a feminine noun in Spanish, so it takes:

• la película
• una película

Adjectives and articles must agree with it:

• la película española
• una película larga

There is no special reason visible from the sentence itself; it is simply the grammatical gender of the noun, and learners need to remember it as part of the word.

A careful Spain Spanish pronunciation would be approximately:

Mi abuelo empezó a roncar en el sofá mientras veíamos la película.

Very roughly for an English speaker:

Mee ah-BWE-lo em-peh-THO ah ron-KAR en el so-FA mee-EN-tras veh-A-mos la peh-LEE-ku-la

A few useful notes for Spain Spanish:

• z in empezó is pronounced like th in thin
• v and b sound very similar in Spanish
• j does not appear here, but g before e/i and j would be a throatier sound in Spain Spanish
• stress falls on:
  • abuelo
  • empezó
  • roncar
  • sofá
  • veíamos
  • película

It follows a very common storytelling pattern in Spanish:

• [completed event in preterite] + mientras + [ongoing background in imperfect]

Here that is:

• Mi abuelo empezó a roncar → completed event, preterite
• mientras veíamos la película → background action, imperfect

This pattern is extremely useful for narrating past events:

• Empezó a llover mientras caminábamos.
• Se apagó la luz mientras cenábamos.
• Sonó el teléfono mientras dormía.

So this sentence is a good model for talking about something that happened while something else was already going on.