Este a lámpa fel van kapcsolva, mert sötét van.

Este means in the evening or at night, depending on context.

In Hungarian, some time words can be used without a case ending as adverbs of time. So:

• este = in the evening
• reggel = in the morning
• délelőtt = before noon
• délután = in the afternoon

So Este a lámpa fel van kapcsolva... is perfectly normal Hungarian word order for In the evening, the lamp is switched on...

A is the definite article, like the in English.

So:

• a lámpa = the lamp
• egy lámpa = a lamp

Hungarian uses articles quite regularly. Here, a lámpa suggests a specific lamp, probably one already known from the situation or context.

Felkapcsolni means to switch on, especially for a light.

It is made of:

• fel = up
• kapcsolni = to switch, connect

Literally, it is something like switch up, but in real usage it means turn on / switch on.

With lights, Hungarian often uses fel:

• felkapcsolni a lámpát = to switch on the lamp
• lekapcsolni a lámpát = to switch off the lamp

So the directional prefix is idiomatic here.

Fel van kapcsolva describes a state, not the action itself.

It means:

• it is switched on
• not someone switches it on

This is a very common Hungarian structure:

• verbal prefix + van
  • verb in -va/-ve

Here:

• fel = prefix
• van = is
• kapcsolva = switched

So A lámpa fel van kapcsolva means The lamp is in the switched-on state.

Compare:

• Felkapcsolják a lámpát. = They switch on the lamp.
• A lámpa fel van kapcsolva. = The lamp is switched on.

Because in this kind of construction, the prefix often stands separately before van.

Base verb:

• felkapcsolni = to switch on

But in the result-state structure:

• fel van kapcsolva

So even though felkapcsolni is one unit as an infinitive, it appears split in this sentence because van is the finite verb.

This is normal Hungarian behavior with verbal prefixes.

The two van forms do two different jobs.

1. A lámpa fel van kapcsolva

Here van is part of the structure meaning is switched on.

2. sötét van

Here van is part of an idiomatic expression meaning it is dark.

So although both are van, they are not doing exactly the same thing.

Because sötét van is a fixed, very common Hungarian way to describe the surrounding condition: it is dark.

Hungarian often uses this pattern for general environmental states:

• meleg van = it is warm
• hideg van = it is cold
• csend van = it is quiet
• sötét van = it is dark

English uses a dummy subject it, but Hungarian does not. So you do not need a word for it here.

No. Sötét van is a special expression about the general environment, not about a specific object.

For a normal adjective sentence with a subject in the present tense, Hungarian usually has no copula:

• A szoba sötét. = The room is dark.
• A lámpa fényes. = The lamp is bright.

But:

• Sötét van. = It is dark.

So sötét van is not just the ordinary adjective pattern.

Sometimes yes, but there is a nuance.

• fel van kapcsolva is especially natural for lights
• be van kapcsolva is very common for devices, machines, electronics

Examples:

• A lámpa fel van kapcsolva. = The lamp is switched on.
• A tévé be van kapcsolva. = The TV is switched on.

For a lamp, be van kapcsolva is understandable, but fel van kapcsolva is often the more idiomatic choice.

Because Hungarian word order is flexible and often puts the topic first.

Here the sentence starts with Este to set the time frame:

• Este = in the evening

Then comes what the sentence is about:

• a lámpa

So the structure feels like:

• As for the evening, the lamp is switched on...

Other word orders are possible, but this one is natural if the speaker wants to begin with the time.

It describes a situation/state.

• fel van kapcsolva = is switched on
• sötét van = it is dark

So the sentence is not focusing on the moment someone turns the lamp on. It is describing the condition: in the evening, the lamp is on because it is dark.

If you wanted to focus on the action, you would use a different form, for example:

• Este felkapcsolják a lámpát, mert sötét van.
  = In the evening, they switch on the lamp because it is dark.