Voy a comprobar si el enchufe funciona antes de encender la lámpara.

This is the very common Spanish structure ir a + infinitive, which is used to talk about a near future or an intended action.

• voy = I go / I am going (from ir, to go)
• a = to
• comprobar = to check / to verify

So:

• Voy a comprobar = I’m going to check

It works like this in other persons too:

• vas a comprobar = you are going to check
• va a comprobar = he/she is going to check
• vamos a comprobar = we are going to check

Spanish often uses this structure where English uses going to.

In this sentence, si means whether.

• Voy a comprobar si el enchufe funciona
  = I’m going to check whether the socket/outlet works

In English, if and whether can sometimes both work, but in Spanish si is the normal word used after verbs like:

• ver = to see
• comprobar = to check
• preguntar = to ask
• saber = to know

Examples:

• No sé si viene. = I don’t know whether he’s coming.
• Pregunta si está abierto. = Ask whether it’s open.

Important: this si has no accent. It is different from sí with an accent, which means yes or oneself in some contexts.

Because enchufe is a masculine noun in Spanish, so it takes el in the singular.

• el enchufe = the plug / socket / outlet
• los enchufes = the plugs / sockets / outlets

This may feel arbitrary to an English speaker, because grammatical gender in Spanish does not always match anything logical in English. You simply need to learn the noun together with its article:

• el enchufe
• la lámpara

That said, the ending -e does not reliably tell you whether a noun is masculine or feminine, so the article is especially important.

In Spain, enchufe can refer to a plug socket / power outlet, and sometimes also to a plug, depending on context.

In this sentence:

• Voy a comprobar si el enchufe funciona...

the most natural meaning is probably socket / outlet, because you are checking whether the power point works before turning on the lamp.

In different contexts, Spanish can distinguish related words like:

• enchufe = plug / socket / outlet
• clavija = plug
• toma de corriente = power outlet

But in everyday Spanish, enchufe is very common and flexible.

Because after si meaning whether, Spanish normally uses the tense that fits the situation directly.

Here:

• si el enchufe funciona
  literally = whether the socket works

Even though the whole sentence is about a future action (I’m going to check), the clause after si uses the present because you are checking its current state.

• funciona = it works / is working
• from funcionar = to work / to function

Spanish does this very naturally:

• Voy a ver si está abierto. = I’m going to see if it’s open.
• Quiero saber si sirve. = I want to know if it works / if it’s any good.

Because after antes you normally use de before an infinitive or noun.

So:

• antes de + infinitive
• antes de + noun

Examples:

• antes de salir = before leaving
• antes de comer = before eating
• antes de la cena = before dinner

That is why:

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

Without de, it would be incorrect here.

Because after antes de, when the subject is the same as in the main clause, Spanish uses the infinitive.

Here, the person doing both actions is the same:

• Voy a comprobar... = I’m going to check...
• antes de encender la lámpara = before turning on the lamp

The implied subject of encender is also I.

This is very common in Spanish:

• Después de comer, salimos. = After eating, we go out.
• Antes de entrar, llamó a la puerta. = Before entering, he knocked on the door.

If the subject changes, Spanish often uses a full clause instead:

• antes de que enciendas la lámpara = before you turn on the lamp

That uses antes de que + subjunctive, because now there is a different subject.

Encender usually means to turn on, to switch on, or to light, depending on what the object is.

Examples:

• encender la lámpara = to turn on the lamp
• encender la luz = to turn on the light
• encender una vela = to light a candle
• encender el fuego = to light the fire

So the basic idea is to make something start giving light, heat, power, etc.

Its opposite is often:

• apagar = to turn off / switch off / extinguish

Example:

• encender la lámpara / apagar la lámpara

Spanish uses definite articles (el, la, los, las) more often than English does.

So Spanish naturally says:

• encender la lámpara
• literally: turn on the lamp

Even if English might sometimes say turn on the lamp or turn on a lamp, Spanish often prefers the article because the object is understood or specific in the situation.

This is very normal with everyday objects:

• Abre la puerta. = Open the door.
• Cierra la ventana. = Close the window.
• Enciende la luz. = Turn on the light.

Yes, but comprobar is a very natural choice here.

Possible options:

• comprobar = to check, verify, make sure
• revisar = to check, inspect, look over
• verificar = to verify, confirm

In this sentence:

• Voy a comprobar si el enchufe funciona

comprobar sounds very good because you are checking whether something works.

Other options might sound slightly different:

• Voy a revisar el enchufe = I’m going to inspect/check the socket
  This can sound a bit more like examining it physically.
• Voy a verificar si el enchufe funciona = I’m going to verify whether the socket works
  Correct, but a bit more formal.

So comprobar is probably the most idiomatic everyday choice here.

Sometimes yes, but the meaning shifts slightly.

• comprobar si funciona = check whether it works
• probar si funciona = test whether it works / try it to see if it works

So probar often suggests a more hands-on test, while comprobar can simply mean checking or verifying.

For example:

• Voy a probar la lámpara. = I’m going to test the lamp.
• Voy a comprobar si el enchufe funciona. = I’m going to check whether the socket works.

Both can be possible depending on what exactly you mean, but comprobar is a very safe and natural choice here.

The given word order is the most natural:

• Voy a comprobar si el enchufe funciona antes de encender la lámpara.

But Spanish does allow some flexibility. For example:

• Antes de encender la lámpara, voy a comprobar si el enchufe funciona.

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

So both are correct:

1. Voy a comprobar si el enchufe funciona antes de encender la lámpara.
2. Antes de encender la lámpara, voy a comprobar si el enchufe funciona.

The difference is mostly about focus and style, not grammar.

For a learner of Spanish from Spain, el enchufe most often corresponds to what many English speakers call:

• socket in British English
• outlet or socket in American English

If you translate it as plug, that can sometimes be confusing in English, because English often distinguishes:

• plug = the part on the cable
• socket/outlet = the place in the wall

Spanish enchufe can blur that distinction more than English does, so context matters. In this sentence, because you are checking whether it works, the most likely English idea is:

• the outlet/socket works

So for understanding this sentence, socket or outlet is probably the best match.