La lampada si spegne quando manca corrente.

The lamp turns off when there is no power.

Breakdown of La lampada si spegne quando manca corrente.

• quando: when
• mancare: to lack
• la lampada: the lamp
• spegnersi: to turn off
• la corrente: the power

Questions & Answers about La lampada si spegne quando manca corrente.

Why does the sentence use si spegne instead of just spegne?

In Italian, spegnere is a transitive verb (it needs an object: you extinguish something). To say “it goes off” or “it turns off” by itself, you use the pronominal (intransitive) form spegnersi. The si is a reflexive/pronominal pronoun that turns spegnere into spegnersi, meaning “to switch off on its own.”

What exactly does manca corrente mean, and why is there no article before corrente?

Here corrente means “electricity” or “power” in an uncountable sense. Uncountable nouns in Italian often drop the article when speaking of them generically. So manca corrente literally means “electricity is missing,” i.e. “there is a power outage.”

What tense and mood is manca?

Manca is the third person singular present indicative of mancare (“to be missing”). So quando manca corrente means “when (electricity) is missing,” or “when there’s no power.”

Could I say La lampada si spegne quando non c’è corrente instead?

Yes. Non c’è corrente uses ci + è to say “there isn’t power.” It’s perfectly natural:
La lampada si spegne quando non c’è corrente.

Can you omit si and use a passive, like “La lampada è spenta quando manca corrente”?

You could, but the meaning shifts slightly.
• La lampada si spegne… describes the action of the lamp turning off.
• La lampada è spenta… describes its state (it is off).
So è spenta quando manca corrente is grammatically fine but focuses on its state rather than the switching‐off event.

How would I express this idea in the past?

You have two main options:
1) Passato prossimo:
La lampada si è spenta quando mancava corrente.
2) Passato remoto (more literary or formal):
La lampada si spense quando mancò corrente.

Is there a synonym for spegnersi in this context?

Yes. You might also say:
• La lampada si disattiva quando manca corrente.
• La lampada si interrompe (less common for a lamp).
But spegnersi is the standard choice for lights and lamps.

What if I want to specify “blackout” instead of “power outage”?

You can use blackout (it’s borrowed into Italian) or interruzione di corrente:
• La lampada si spegne durante il blackout.
• La lampada si spegne quando c’è un’interruzione di corrente.