A függöny hosszú, és jól mutat a nappaliban.

In Hungarian, the verb van (to be) is usually left out in the present tense, third person when one noun or adjective is describing another.

So:

• A függöny hosszú. = The curtain is long.
• not normally A függöny van hosszú.

You would use forms of van in other situations, for example:

• A függöny hosszú volt. = The curtain was long.
• A függöny hosszú lesz. = The curtain will be long.

This is one of the most common things English speakers notice in Hungarian.

A is the definite article, meaning the.

In this sentence:

• A függöny = the curtain
• a nappaliban = in the living room

Hungarian uses definite articles very regularly, often in places where English also uses the. So having it twice is completely normal because there are two separate nouns:

• függöny = curtain
• nappali = living room

Also note:

• a is used before consonant sounds
• az is used before vowel sounds

For example:

• a ház = the house
• az asztal = the table

Függöny means curtain.

Its pronunciation may look difficult at first because of the Hungarian letters:

• ü is a front rounded vowel, somewhat like the German ü
• gg is a long/doubled g
• ny is pronounced like the ny in Spanish señor, or like ny in canyon

A rough learner-friendly approximation might be something like:

• füg-göny

But it is best to learn the actual Hungarian sounds, especially ü and ny, because they are very common.

Hosszú means long.

It is simply the normal dictionary form of the adjective. The -ú here is not a suffix you need to separate off in this sentence; it is just part of the word.

A few useful notes:

• sz in Hungarian is pronounced like English s
• hosszú is pronounced roughly like hoss-soo
• the final ú is a long vowel, so it is held a bit longer than u

Hungarian spelling marks vowel length very clearly, and length can matter:

• u and ú are different vowels in length
• o and ó, ö and ő, etc., also differ

Because jól is an adverb, while jó is an adjective.

• jó = good
• jól = well

In this sentence, mutat is a verb, so it is being modified by an adverb:

• jól mutat = looks good / looks nice / suits the setting well

Compare:

• jó függöny = a good curtain
  here jó describes a noun
• A függöny jól mutat. = The curtain looks good.
  here jól modifies a verb

This is similar to English good vs well, though usage is not always perfectly parallel.

Yes, mutat often means show, point, or indicate, but in some contexts it also means something like:

• look
• look good
• appear
• suit the surroundings

So jól mutat is a very natural Hungarian expression meaning:

• looks good
• looks nice
• works well visually

In this sentence, A függöny hosszú, és jól mutat a nappaliban, jól mutat is about appearance in the room, not about literally showing something.

A nappaliban means in the living room.

It has three parts:

• a = the
• nappali = living room
• -ban = in

So:

• nappaliban = in the living room

The ending -ban/-ben is called the inessive case, and it expresses being inside something.

Examples:

• a házban = in the house
• a szobában = in the room
• a nappaliban = in the living room

Because of vowel harmony.

Hungarian suffixes often change depending on the vowels in the word. A simplified version is:

• back-vowel words usually take -ban
• front-vowel words usually take -ben

Nappali contains back vowels (a, a), so it takes:

• nappaliban

Compare:

• házban = in the house
• kertben = in the garden
• székben = in the chair

Vowel harmony is a major part of Hungarian grammar, and this sentence gives you a very common example of it.

Good question. Nappali is related to day/daytime, and depending on context it can have different meanings.

As a noun, nappali commonly means:

• living room

As an adjective, it can relate to:

• daytime
• daily
• day-...

So context matters. In this sentence, because it appears with the article and location ending:

• a nappaliban

it clearly means:

• in the living room

Because és is joining two clauses here.

The sentence has two parts:

• A függöny hosszú
• (és) jól mutat a nappaliban

Hungarian often uses a comma before és when it connects two clauses with separate predicates. Even though the first clause has no written van, it is still a full clause:

• A függöny hosszú = The curtain is long.

So the comma is normal here.

Yes. Hungarian word order is flexible, and changing it often changes the focus or emphasis, not the basic meaning.

The neutral version here is:

• A függöny hosszú, és jól mutat a nappaliban.

But you could also say, for example:

• A nappaliban jól mutat a függöny.
  = It’s in the living room that the curtain looks good.

This puts more attention on a nappaliban.

Or:

• Jól mutat a függöny a nappaliban.
  = The curtain looks good in the living room.

This can sound slightly more focused on jól mutat.

So yes, the order can change, but the neutral sentence given is a very natural starting point.

A rough pronunciation guide:

• A függöny hosszú, és jól mutat a nappaliban.
• roughly: aw füg-göny hos-soo, aysh yohl moo-tawt aw nop-paw-lee-bawn

A few key pronunciation points:

• stress is normally on the first syllable of each word
• sz = English s
• s = English sh
• ny = like Spanish ñ
• gy = a soft sound, somewhat like the d in British duke
• jól starts with j, which sounds like English y
• ö and ü are front rounded vowels and may need practice

If you want to sound natural, focus especially on:

• vowel length: hosszú, jól
• special consonants: ny
• first-syllable stress in every word