Nyáron este sokáig ülünk az erkélyen, és a várost nézzük.

Because Hungarian often uses a case ending to express time.

• nyár = summer
• nyáron = in summer / during the summer

The ending here is -on, one form of the -on/-en/-ön/-n suffix. With seasons, some time expressions are idiomatic, so you learn them as set forms:

• nyáron = in summer
• télen = in winter
• tavasszal = in spring
• ősszel = in autumn

So in this sentence, nyáron is a time expression, not a location.

In Hungarian, este can work as an adverb meaning in the evening / in the evenings, especially in everyday language.

So Nyáron este is very natural and usually means something like:

• In summer, in the evening
• or more idiomatically in English, On summer evenings

Because the verb is in the present tense and the sentence sounds like a general description, the whole sentence is usually understood as a habit, not a one-time event.

If you wanted to make the repeated meaning extra explicit, Hungarian could also use esténként = every evening / evenings.

sokáig means for a long time or until late, depending on context.

In this sentence, it suggests that they stay sitting on the balcony for quite a while in the evening. So the feeling is:

• we sit there for a long time
• possibly we stay out late

It is an adverb, so it describes how long the action lasts.

ülünk comes from ülni = to sit.

The ending -ünk shows:

• 1st person plural
• present tense

So ülünk = we sit or we are sitting.

A very important point for English speakers: Hungarian simple present can cover both the English simple present and present progressive, depending on context.

So ülünk can mean:

• we sit
• we are sitting

Here, because the sentence sounds habitual, English would usually translate it as we sit.

There are two things happening here:

1. az is the definite article
   Hungarian has two forms of the:

   • a before a consonant sound
   • az before a vowel sound

   Since erkély begins with a vowel sound, you say az erkély.

2. -en marks location
   erkélyen means on the balcony.

So:

• erkély = balcony
• az erkélyen = on the balcony

This suffix is one of the common Hungarian location endings, roughly matching English on in this case.

Because várost is the direct object of the verb nézzük.

Hungarian marks the direct object with the accusative ending -t:

• város = city
• várost = city as a direct object

So:

• a várost nézzük = we are looking at the city

English uses look at, but Hungarian nézni usually takes a direct object directly, without a separate word for at.

This is because Hungarian has two kinds of verb conjugation:

• indefinite conjugation
• definite conjugation

Since the object is a várost = the city, which is definite, the verb also appears in the definite conjugation.

So:

• nézünk = we look / we are looking, with no definite object or with an indefinite one
• nézzük = we look at it / we are looking at the definite object

That is why the sentence uses nézzük.

Hungarian word order is much more flexible than English word order. It is guided a lot by topic and focus, not just by subject-verb-object order.

Both of these are possible:

• nézzük a várost
• a várost nézzük

The version in your sentence puts a várost before the verb, which makes it feel more like the topic or the thing being talked about. It is natural in a descriptive sentence like this.

A simple way to think about it:

• nézzük a várost = neutral we look at the city
• a várost nézzük = the city is a bit more foregrounded

In real usage, the difference may be small, especially in writing, but Hungarian speakers do use word order to shape emphasis and information flow.

Because Hungarian often leaves out subject pronouns when the verb ending already makes the subject clear.

Both verbs already show we:

• ülünk = we sit
• nézzük = we look at it / we look at the definite object

So adding mi = we is usually unnecessary.

Hungarian would only add mi if the speaker wanted special emphasis or contrast, for example:

• Mi ülünk az erkélyen = We are the ones sitting on the balcony

This is very different from English, where the subject pronoun is usually required.

Because és is joining two full clauses, each with its own verb:

• ülünk = we sit
• nézzük = we look

In Hungarian, when coordinating full clauses like that, a comma is normally used before és.

Compare:

• Nyáron este sokáig ülünk az erkélyen, és a várost nézzük.
  Two clauses → comma

But:

• nyáron és ősszel
  Just two words/phrases → no comma

So the comma is there because the sentence contains two coordinated actions.