Learn Hardcore Hungarian: A jegypénztárnál sok külföldi turista áll sorban, mert pénteken kevés vonat indul. - At the ticket office many foreign tourists are standing in line because on Friday few trains depart.

You use -nál / -nél for being at some place (often a smaller, more point-like place, office, person, desk, etc.), rather than inside it. If you said jegypénztárban, that would be more like “inside the ticket office (room/booth).”

Why is it sok külföldi turista and not sok külföldi turisták?

With quantity words like sok (many), kevés (few), három (three), etc., Hungarian normally keeps the noun in the singular:

sok turista = many tourists
kevés vonat = few trains
három ember = three people

So you do not add the plural -k after sok.
sok turisták is wrong in standard Hungarian.

What does sorban áll literally mean, and how does it work as an expression?

Literally:

sor = line, row
sorban = in/into a line
áll = stands

So sorban áll literally means “stands in a line”, and idiomatically it means “to stand in line / to queue.”

It’s a fixed verb + adverbial expression. You generally keep sorban and áll together in that order to mean “to queue.”

Could I say sorban vannak instead of áll sorban?

Not in normal Hungarian for the meaning “to be standing in a line.”

áll sorban or sorban áll = stands in line, is queuing
vannak sorban would sound odd and is not the standard way to say “they are in a line / they are queuing.”

Use (sorban) állni as the verb for standing in line.

Why is the word order A jegypénztárnál sok külföldi turista áll sorban and not Sok külföldi turista áll sorban a jegypénztárnál?

Both sentences are possible; they just have different emphasis.

A jegypénztárnál sok külföldi turista áll sorban
→ Topic: as for the ticket office / at the ticket office…
You first set the location as the topic, then comment what’s happening there.
Sok külföldi turista áll sorban a jegypénztárnál
→ Topic: as for the many foreign tourists…
Now the tourists are the starting point, and you add where they are.

Hungarian word order is heavily driven by topic–comment and focus, not just by a fixed SVO pattern like English.

What does külföldi mean, and does it change form?

külföldi can be:

An adjective: foreign
- külföldi turista = foreign tourist
A noun: foreigner
- sok külföldi = many foreigners

As an adjective before a noun, it does not change form for gender or number:

egy külföldi turista = a foreign tourist
sok külföldi turista = many foreign tourists

The plural is understood from sok + the context.

What does mert do in this sentence, and why is there a comma before it?

mert means “because.” It introduces a reason clause:

… áll sorban, mert pénteken kevés vonat indul.
= … are standing in line, because few trains depart on Friday.

Hungarian usually puts a comma before mert when it links two clauses, similar to English:

… , mert … = …, because …

What is the role of -en in pénteken?

péntek = Friday
pénteken = on Friday

The ending -n / -on / -en / -ön is often used to form time expressions, roughly like English “on (a day)”:

hétfőn = on Monday
szombaton = on Saturday
pénteken = on Friday

So pénteken means “on Friday”.

Why is it kevés vonat indul and not kevés vonatok indulnak?

Two points:

With quantity words like kevés (few), the noun stays singular:
- kevés vonat, not kevés vonatok
When the subject is a quantified noun phrase like sok / kevés / három + noun, the verb often appears in the 3rd person singular:
- Kevés vonat indul. = Few trains depart.
- Sok ember jön. = Many people are coming.

So kevés vonat indul is grammatically normal and idiomatic.

What exactly does indul mean here? Is it only “to start”?

indul means “to depart, to set off, to leave” (for vehicles, people, etc.).

In this sentence:

kevés vonat indul = few trains depart / leave

It often corresponds to English “the train leaves/departs at…”:

A vonat nyolckor indul. = The train leaves at eight.

Why is Hungarian using a simple present (áll, indul) where English would say “are standing” and “leave”?

Hungarian does not have a separate continuous tense like English (am standing, are leaving). The simple present can cover both:

sok turista áll sorban
→ “many tourists stand in line” or “many tourists are standing in line”

The exact reading (habitual vs right now) comes from context, not from a different tense form. The same for indul: context tells you whether it’s a schedule or a one-time event.

Could I put mert pénteken kevés vonat indul at the beginning of the sentence?

Yes:

Mert pénteken kevés vonat indul, a jegypénztárnál sok külföldi turista áll sorban.

This is also grammatical. The difference is in discourse flow:

Original: A jegypénztárnál…, mert…
→ Starts with the situation at the ticket office, then gives the reason.
Reordered: Mert pénteken kevés vonat indul…
→ Starts with the reason, then states the consequence.

Both are acceptable; you choose based on what you want to highlight first.

Is there any difference between pénteken kevés vonat indul and kevés vonat indul pénteken?

Both are correct and mean the same in neutral context:

pénteken kevés vonat indul
kevés vonat indul pénteken

Hungarian allows flexible word order. Subtle differences in focus or rhythm can appear:

Starting with pénteken highlights the day.
Starting with kevés highlights the small number of trains.

But in many everyday contexts, they are interchangeable.

Could jegypénztár be replaced by something shorter like pénztár here?

Yes, often you’ll hear:

A pénztárnál sok külföldi turista áll sorban…

pénztár on its own means cash desk / ticket office / cashier’s, depending on context.
jegypénztár is more explicitly “ticket office” (literally “ticket-cash desk”), but in a station context pénztár is usually understood as the ticket office.