A lakosság fiatal.

In Hungarian, the verb to be is usually left out in the present tense when the subject is third person singular or plural.

So:

• A lakosság fiatal. = The population is young.
• literally: The population young.

But in other persons, Hungarian does use the verb:

• Fiatal vagyok. = I am young.
• Fiatal vagy. = You are young.

This is a very common feature of Hungarian.

A is the definite article, meaning the.

So:

• a lakosság = the population

Hungarian has two forms of the definite article:

• a
• az

Which one is used depends on the following sound:

• a lakosság
• az ember

A very rough rule is:

• use a before consonant sounds
• use az before vowel sounds

Since lakosság starts with l, it takes a.

Because lakosság is a collective noun. It means population, residents, or the body of inhabitants as one group.

So even though it refers to many people, grammatically it is singular:

• A lakosság fiatal. = The population is young.

This is similar to English the population, which is also grammatically singular in many contexts.

It is in the nominative case, which is the basic dictionary form and the usual case for the subject of a sentence.

In this sentence:

• A lakosság = the subject
• fiatal = the predicate adjective

No special case ending is needed here.

Hungarian adjectives do not agree with nouns the way they do in many Indo-European languages.

That means the adjective does not change for:

• gender
• singular/plural
• definiteness

So fiatal stays fiatal.

Examples:

• A lány fiatal. = The girl is young.
• A fiúk fiatalok. = The boys are young.

Notice that in predicate position, plural can appear on the adjective:

• fiatalok

But with a singular noun like lakosság, you use:

• fiatal

A helpful approximate pronunciation is:

• lakosság ≈ LAW-kosh-shaag
• fiatal ≈ FEE-ya-tawl

A few useful points:

• Hungarian stress is almost always on the first syllable.
• s in Hungarian sounds like English sh.
• sz sounds like English s.
• á is a long vowel, somewhat like a in father, but longer.
• fi in fiatal is usually pronounced like fee.

So:

• LA-kos-ság
• FI-a-tal

Yes. Hungarian word order is flexible, and changing the order often changes the focus or emphasis.

• A lakosság fiatal. = neutral statement, The population is young.
• Fiatal a lakosság. = puts more emphasis on young

So the second version can sound a bit like:

• The population is young
• or It is young, the population

Both are grammatical, but A lakosság fiatal is the most neutral form.

They are similar, but not always identical in feel.

• lakosság often means the inhabitants/resident population of a place
• népesség often sounds more demographic/statistical, meaning population in a broader or more formal sense

In many sentences they can overlap, but lakosság is very natural when talking about the people living in a town, region, or country.

Not exactly. It means the population is young, not simply there are young people there.

It describes the overall age profile of the population. In other words, it suggests that, on average or as a group, the inhabitants are relatively young.

So it is more like:

• The population is youthful
• The population is young overall

rather than:

• There are young people there

Normally, no.

• a lakosság = the population
• egy lakosság would mean a population, which is much less natural in a simple sentence like this

Since we are talking about a specific population, the definite article a is the normal choice.

So:

• A lakosság fiatal. = natural
• Egy lakosság fiatal. = unnatural in ordinary use

In this sentence, fiatal is an adjective meaning young.

Here it works as a predicate adjective, describing the subject:

• A lakosság fiatal.

But Hungarian adjectives can often behave in noun-like ways too, depending on the context. For example:

• a fiatalok = the young people

So fiatal is basically an adjective, but Hungarian can use adjectives quite flexibly.