Apago la luz de la sala antes de dormir.

I turn off the light in the living room before sleeping.

Breakdown of Apago la luz de la sala antes de dormir.

• yo: I
• de: of
• dormir: to sleep
• antes: before
• la sala: the living room
• apagar: to turn off
• la luz: the power

Questions & Answers about Apago la luz de la sala antes de dormir.

Why is it apago and not apagar in this sentence?

Apagar is the infinitive form of the verb (to turn off).
Apago is the verb conjugated for:

• 1st person singular (I)
• Present indicative (present tense)

So:

• Apago la luz… = I turn off the light… / I am turning off the light…

Using apago indicates:

• who does the action: I
• when: in general right now or as a habit (e.g., every night)

If you used the infinitive apagar, it would be like saying to turn off the light…, which is not a complete sentence in Spanish.

Do I need to say yo apago or is apago alone enough?

You usually don’t need to say yo.

In Spanish, the verb ending (-o in apago) already shows the subject is yo (I), so:

• Apago la luz de la sala antes de dormir. = I turn off…
• Yo apago la luz de la sala antes de dormir. = same meaning, but with extra emphasis on I.

You typically add yo only for:

• Emphasis/contrast:
  Yo apago la luz, tú cierras la puerta.
  I turn off the light, you close the door.
• Clarity, if there could be confusion about who does the action.

In neutral, everyday speech, Apago la luz… is perfectly natural and is actually more common than Yo apago la luz….

Why is it la luz and not just luz or mi luz?

Spanish normally uses an article with countable nouns like luz when you mean a specific one.

• la luz = the light (a specific, known light)
• Saying apago luz (no article) is not natural in standard Spanish; it sounds like telegraphic speech.

Mi luz (my light) would change the meaning. It sounds like:

• my electric power service, or
• my lamp/light (as my possession), not just the light in the living room.

Here you are referring to that specific light that belongs to the living room, so la luz is the normal, idiomatic choice.

Grammar note:

• luz is feminine, so it takes la.
• Plural: luces (z → c + es).

What exactly does sala mean here? Is it “room” or “living room”?

In Latin American Spanish, la sala almost always refers to the living room (the place with the sofa, TV, etc.), unless context clearly says otherwise.

So:

• la luz de la sala ≈ the living-room light.

Regional note:

• In much of Spain, people more often say el salón for living room:
  • Apago la luz del salón antes de dormir.

But in Latin America, la sala is very common and natural for living room.

Why is it de la sala and not en la sala?

De la sala literally means “of the living room”, and it indicates possession/belonging:

• la luz de la sala = the living-room light
  (the light that belongs to / is associated with the living room)

En la sala means “in the living room”, describing location, not possession:

• la luz en la sala = the light in the living room
  (the light that is located there, but it sounds less like the main room light as a fixture)

In practice:

• When you talk about fixtures or parts of a room, de is the normal choice:
  
  • la puerta de la cocina – the kitchen door
  • el techo del baño – the bathroom ceiling
  • la luz de la sala – the living-room light

You could say la luz en la sala, but here de la sala is more idiomatic and sounds like “the light that belongs to that room.”

Can I make luz plural and say Apago las luces de la sala?

Yes. You use the plural when there is more than one light source in the room:

• Apago la luz de la sala…
  = I turn off the light (one main light).
• Apago las luces de la sala…
  = I turn off the lights (several bulbs/fixtures).

Grammar:

• Singular: la luz
• Plural: las luces (z → c + es: luz → luces)

Why is it antes de dormir and not antes dormir or antes que dormir?

In this structure, antes de is required:

• antes de
  • noun / infinitive
• antes de dormir = before sleeping / before going to sleep

So:

• antes dormir ❌ (incorrect; it needs de)
• antes que dormir ❌ (not used in this meaning)

Use:

• antes de
  • infinitive → when it’s followed directly by a verb:
    • antes de comer, antes de salir, antes de dormir

Why is it dormir (infinitive) and not duermo (I sleep)?

After a preposition (like de), Spanish almost always uses the infinitive, not a conjugated verb.

Here:

• antes de dormir
  
  • antes de = preposition
  • dormir = infinitive → required after the preposition

Meaning:

• Apago la luz… antes de dormir.
  = I turn off the light… before sleeping / before I go to sleep.

Also, because the subject is the same in both actions (I turn off / I sleep), Spanish uses:

• antes de
  • infinitive (dormir)

If the subject changed, you’d use antes de que + subjunctive:

• Apago la luz antes de que mis hijos duerman.
  I turn off the light before my children sleep.

Can I change the word order to Antes de dormir, apago la luz de la sala?

Yes. That word order is completely correct:

• Antes de dormir, apago la luz de la sala.
• Apago la luz de la sala antes de dormir.

Both mean the same. The difference is only emphasis:

• Starting with Antes de dormir puts a bit more focus on the time condition (Before sleeping, …).

Other options:

• Apago la luz de la sala, antes de dormir. ✔ (also possible, slightly more “afterthought” style)
• Apago antes de dormir la luz de la sala. ✔ but sounds a bit awkward/less natural in everyday speech.

The most natural are:

• Apago la luz de la sala antes de dormir.
• Antes de dormir, apago la luz de la sala.

How would I say this if I’m talking about a specific time in the past?

You would normally use the preterite for a finished past action:

• Ayer apagué la luz de la sala antes de dormir.
  Yesterday I turned off the living-room light before sleeping.

Changes:

• apago (present) → apagué (1st person singular preterite)
• The spelling changes from g to gu (apagué) to keep the same sound.

So:

• Apago la luz… = I (usually / right now) turn off the light…
• Apagué la luz… = I turned off the light (on that occasion).

Can I replace la luz de la sala with a pronoun and say La apago antes de dormir?

Yes, that’s very natural if it’s clear from context which light you mean.

• La apago antes de dormir.
  = I turn it off before sleeping.

Here:

• la is the direct object pronoun for a feminine singular noun (la luz).
• It goes before the conjugated verb: La apago…

Typical usage:

1. First mention the noun:
   • Apago la luz de la sala todas las noches.
2. Later, just refer to it with the pronoun:
   • Siempre la apago antes de dormir.

Is there a difference between apagar la luz, apagar la lámpara, and apagar las luces?

Yes, it’s mostly about what exactly you’re referring to:

• apagar la luz
  = turn off the light (the room’s lighting in general; very common)
• apagar la lámpara
  = turn off the lamp (a specific lamp or fixture)
• apagar las luces
  = turn off the lights (several light sources)

All are grammatically correct; you choose based on what you mean:

• If you’re just talking about lighting in the living room in general, apagar la luz de la sala is the most common and neutral.
• If you want to be more specific (for example there are many lamps), you might say apagar la lámpara de la sala or apagar las luces de la sala.

What’s the difference between apagar la luz and la luz se apaga?

The difference is who is doing the action:

1. Apago la luz de la sala antes de dormir.

   • apagar is a transitive verb here (needs a direct object: la luz)
   • Meaning: I actively turn the light off.

2. La luz se apaga.

   • apagarse is the pronominal/reflexive form.
   • Meaning: The light turns off / goes out (by itself or with no specific subject mentioned; maybe automatically, or it suddenly fails).

So:

• Use apagar la luz when you or someone specific does the action.
• Use la luz se apaga when the light goes off on its own, or when you don’t care who/what caused it.