Cuando se va la luz en la casa, encendemos la linterna.

When the power goes out at home, we turn on the flashlight.

Breakdown of Cuando se va la luz en la casa, encendemos la linterna.

• nosotros: we
• cuando: when
• la casa: the house
• en: at
• encender: to turn on
• la linterna: the flashlight
• irse la luz: the power goes out

Questions & Answers about Cuando se va la luz en la casa, encendemos la linterna.

What does “se va la luz” literally mean, and why is it used for a power cut?

Literally, “se va la luz” is something like “the light goes away / leaves”.

In everyday Latin American Spanish, this expression is the common, natural way to say that the electricity goes out (a power outage). It doesn’t mean that the sunlight moves; it specifically refers to electric power being cut off, so all the lights at home go out.

You’ll also hear related phrases like:

• Se fue la luz. – The power went out.
• No hay luz. – There’s no power / electricity.
• Se cortó la luz. – The power was cut.

Why do we need “se” in “se va la luz”? Why not just “va la luz”?

The “se” here is part of the verb irse (“to go away / to leave”), not the simple verb ir (“to go”).

• ir = to go (usually with a destination: va al trabajo – “he goes to work”)
• irse = to go away, to leave (from a place: se va de la casa – “he leaves the house”)

So:

• La luz se va. = The light/electricity leaves (goes away).
• La luz va. sounds incomplete or strange; you’d expect “va a algún lado” (“goes to somewhere”).

Using irse with things that disappear by themselves (water, electricity, people leaving a place) is very common in Spanish:

• El agua se fue. – The water ran out.
• La gente se fue. – The people left.
• Se va la luz. – The power goes out.

Can I also say “Cuando la luz se va en la casa…” instead of “Cuando se va la luz en la casa…”?

Yes, both word orders are grammatically correct:

• Cuando se va la luz en la casa…
• Cuando la luz se va en la casa…

Spanish allows some flexibility in where you place the “se” + verb and the subject (la luz).

However, in many regions, the expression “se va la luz” is a very fixed, common chunk. That’s why “Cuando se va la luz…” sounds more idiomatic and natural than “Cuando la luz se va…”, even though both are fine.

Why is the verb in the present tense (se va / encendemos) if this talks about something that happens at different times, including the future?

In Spanish, the present tense is often used for:

1. Habitual actions (things that happen regularly)
2. General truths / typical situations

Here, the sentence describes what you typically do whenever the power goes out. So Spanish uses the present indicative:

• Cuando se va la luz en la casa, encendemos la linterna.
  = Whenever the power goes out at home, we turn on the flashlight.

English often uses the present too in this kind of sentence (“When the power goes out, we turn on the flashlight”), so the logic is actually quite similar: present tense for a general rule.

Should it be “Cuando se vaya la luz…” with the subjunctive instead of “Cuando se va la luz…”?

Both are possible, but they’re used in different situations.

1. Habitual / general situation → Indicative
   When you’re talking about what usually happens (a rule or routine), you use the present indicative:

   • Cuando se va la luz, encendemos la linterna.
     (Whenever the power goes out, we turn on the flashlight.)

2. A future, specific, not-yet-real event → Subjunctive
   When you talk about a future event that hasn’t happened yet, especially in combination with a future verb in the main clause, Spanish normally uses subjunctive after cuando:

   • Cuando se vaya la luz, vamos a encender la linterna.
     When the power goes out, we’re going to turn on the flashlight.
     (Talking about a particular future situation you’re imagining or planning for.)

In everyday speech, many native speakers use the indicative here even with future meaning, but the textbook rule is:

• Habit / general statement → indicative (se va)
• Future, specific, not yet realized event → subjunctive (se vaya)

Why don’t we say “nosotros encendemos”? Why is there no subject pronoun?

Spanish is a “pro‑drop” language, which means it usually omits subject pronouns because the verb form already tells you who the subject is.

• encendemos already contains the information “we turn on”.

• Adding nosotros is normally only for emphasis, contrast, or clarity:

  • Nosotros encendemos la linterna (y ellos encienden las velas).
    We turn on the flashlight (and they light candles).

In your sentence, there’s no contrast needed, so the most natural version is:

• …encendemos la linterna. (without nosotros).

What’s the difference between “encender” and “prender”? Could I say “prendemos la linterna” instead?

In this context, “encender” and “prender” usually mean the same thing: to turn on / to switch on (a light, device, etc.).

• encender la linterna
• prender la linterna

Both are understood as “turn on the flashlight”.

Regional/usage notes:

• encender is more standard / neutral and is understood everywhere.
• prender is extremely common in many parts of Latin America in everyday speech:
  • prender la luz, prender la tele, prender el carro, etc.

So yes, “Cuando se va la luz en la casa, prendemos la linterna” is perfectly natural in much of Latin America.

Why is it “la linterna” with “la”? Could I drop the article and just say “encendemos linterna”?

You can’t drop the article here; “encendemos linterna” is ungrammatical in standard Spanish.

In Spanish, when you talk about a specific, known object, you normally use the definite article:

• la linterna – the flashlight (the one we always use)
• la luz – the power / electricity

If you said “una linterna”, it would mean “a flashlight”, introducing it as something new or not specific:

• Cuando se va la luz, encendemos una linterna.
  When the power goes out, we turn on a flashlight. (any flashlight, not a particular known one)

In your sentence, it sounds like a specific flashlight you keep at home, so “la linterna” is the natural choice.

Does “linterna” mean “lantern” or “flashlight” in Latin America?

In most of the Spanish‑speaking world, including Latin America, “linterna” is commonly used for a flashlight (a small, portable light you hold in your hand).

Depending on the country, you may also hear:

• linterna – flashlight (standard)
• linterna de mano – handheld flashlight (more explicit)
• foco – in some places can mean “lightbulb” and sometimes casually “flashlight”
• lámpara – usually “lamp”, but can sometimes be used for portable lights, especially if they’re bigger.

For your sentence, “la linterna” is the standard and clear way to say “the flashlight”.

Why is it “en la casa” and not “a la casa” or just “en casa”?

Because we’re talking about location, not movement.

• en la casa = in the house / at the house (location)
• a la casa = to the house (direction/movement)
• en casa = at home (more general, without specifying “the house” as an object)

So:

• Cuando se va la luz en la casa…
  When the power goes out in the house…

You could also say:

• Cuando se va la luz en casa, encendemos la linterna.

This sounds like “when the power goes out at home…”
Both “en casa” and “en la casa” are correct; “en la casa” is just a bit more specific/physical: in the house.

Why do we say “la luz” (singular) when in English we often say “the lights go out” (plural)?

Spanish often treats “la luz” as a kind of mass/uncountable noun meaning “electricity / electric light in general”.

• Se va la luz.
  Literally: The light goes away.
  Meaning: The power goes out.

In English, it’s very natural to say “the lights go out” (plural lights in the house), but in Spanish:

• la luz (singular) = the electric light / power in general.
• las luces (plural) = the individual lights, bulbs, streetlights, etc.

So:

• Se van las luces de la ciudad. – The city lights go out. (many individual lights)
• Se va la luz en la casa. – The power goes out in the house. (electricity in general)

In your sentence, we’re talking about power in the house as a whole, so singular “la luz” is used.

Could this sentence also mean “when we turn off the light” instead of a power cut?

No. “Cuando se va la luz…” clearly suggests that the power goes out by itself, not that you are turning it off.

• se va la luz = the power goes out (involuntary, external event)
• apagamos la luz = we turn off the light (voluntary action by us)

If you wanted the meaning “when we turn off the lights in the house, we turn on the flashlight”, you’d need something like:

• Cuando apagamos las luces en la casa, encendemos la linterna.

That describes a deliberate action (you switch off the lights), while “se va la luz” is more like a blackout / outage that just happens.