El electricista revisa el enchufe antes de encender la lámpara.

Revisa is the present tense form of the verb revisar for él/ella/usted.

• revisar = to check / to inspect
• revisa = he/she checks

So:

• El electricista revisa... = The electrician checks...

You use revisa because the subject is el electricista, which is third person singular.

Usually, no. This is a very common false friend.

In Spanish, revisar usually means:

• to check
• to inspect
• to examine
• to look over

So here revisa el enchufe means checks the plug/socket/outlet, not revises it.

If you want revise in the sense of studying again, Spanish often uses repasar.

Electricista is one of those nouns that can refer to either a man or a woman. The article tells you the gender of the person:

• el electricista = the male electrician
• la electricista = the female electrician

So electricista itself does not change here; only the article changes.

In Spain, enchufe commonly refers to an electrical plug or socket/outlet, depending on context.

In this sentence, revisa el enchufe most naturally means the electrician checks the electrical connection point before turning on the lamp.

A related term is:

• toma de corriente = power outlet / socket

But enchufe is very common in everyday Spanish in Spain.

Because antes needs de before an infinitive.

The pattern is:

• antes de + infinitive

So:

• antes de encender = before turning on
• antes de salir = before leaving
• antes de comer = before eating

If a full clause follows, Spanish often uses:

• antes de que + subjunctive

For example:

• antes de que encienda la lámpara

But in your sentence, the infinitive structure is the natural one.

Because after antes de, Spanish normally uses the infinitive when the subject is general or understood from context.

So:

• antes de encender la lámpara = before turning on the lamp

This works like English before turning on...

You are not making encender the main verb of the sentence. The main verb is revisa. The infinitive phrase just tells us when that action happens.

Yes. Encender is the normal verb for turn on, especially for:

• lights
• electrical devices
• fire
• cigarettes, etc.

So:

• encender la lámpara = turn on the lamp
• encender la luz = turn on the light
• encender el ordenador = turn on the computer

The opposite is apagar:

• apagar la lámpara = turn off the lamp

Because Spanish uses articles very naturally with specific nouns.

In this sentence, all three nouns are understood as specific things in the situation:

• the electrician
• the plug/socket
• the lamp

So the definite articles are completely normal.

Also, Spanish often uses articles in places where English might sometimes leave them out, but in this sentence English would also usually use the.

Only partly. Noun gender in Spanish is not always predictable just from meaning.

Here:

• el enchufe = masculine
• la lámpara = feminine

Lámpara ends in -a, so feminine is not surprising.

But enchufe ends in -e, and nouns ending in -e can be either masculine or feminine. So you usually need to learn the article with the noun:

• el enchufe
• la lámpara

That is the safest habit.

Yes. Spanish word order is fairly flexible.

You can also say:

• Antes de encender la lámpara, el electricista revisa el enchufe.

This means the same thing, but it puts more emphasis on the time phrase before turning on the lamp.

The original sentence is perfectly natural, though.

It could be either, depending on context.

El electricista revisa el enchufe antes de encender la lámpara can mean:

• a habitual action: this is what the electrician usually does
• a narrative present: this is what happens in the scene

Spanish present tense often works like English present tense in this way.

If you wanted a completed past action, you would change the verb:

• El electricista revisó el enchufe antes de encender la lámpara.

This is useful in Spain Spanish:

• lámpara = lamp
• bombilla = light bulb

So in your sentence, la lámpara means the whole lamp, not just the bulb.

If you said encender la bombilla, that would sound less natural in many contexts unless you were specifically talking about the bulb itself.

You might hear prender in some Spanish-speaking countries, but in Spain, encender is the more standard and expected choice for turn on.

So for Spain Spanish, this is best:

• encender la lámpara

rather than:

• prender la lámpara

Only the article would need to change:

• La electricista revisa el enchufe antes de encender la lámpara.

Everything else stays the same.

That is because electricista is the same form for both genders in this use.