A férfi a kulcsát a fiókba teszi.

Because Hungarian uses the definite article a / az before nouns much like English uses the.

So here:

• a férfi = the man
• a kulcsát = his key / the key of his
• a fiókba = into the drawer

Hungarian normally puts the article before each definite noun phrase, not just once for the whole sentence.

Also, a is used before consonants, while az is used before vowels.

Kulcsát breaks down like this:

• kulcs = key
• kulcsa = his/her/its key
• kulcsát = his/her/its key as a direct object

The final -t is the accusative ending, which marks the direct object.

So in this sentence, a kulcsát means his key or her key, depending on context. Since the subject is the man, the most natural interpretation is his key.

A useful thing to notice: in Hungarian, possession is usually shown on the noun itself, not with a separate word like his before it.

Because Hungarian usually expresses possession with a suffix attached to the noun.

For example:

• kulcs = key
• kulcsom = my key
• kulcsod = your key
• kulcsa = his/her key

So instead of saying something like his key with a separate possessive word, Hungarian often just says kulcsa.

If you want extra emphasis, Hungarian can add a separate possessor:

• a férfi kulcsa = the man's key
• az ő kulcsa = his/her key (emphatic)

But in your sentence, that is not necessary.

Because the noun is the direct object of the verb teszi.

Hungarian marks direct objects with the accusative ending -t. With possessed nouns, this often causes a vowel change in spelling:

• kulcsa = his/her key
• kulcsát = his/her key as object

So the sentence is literally structured something like:

• The man his-key-ACC into-the-drawer puts

That -t is one of the most important case endings in Hungarian.

Because -ba / -be means into, while -ban / -ben means in.

So:

• fiókba = into the drawer
• fiókban = in the drawer

Since the sentence describes movement toward the inside of the drawer, Hungarian uses -ba.

Compare:

• A férfi a kulcsát a fiókba teszi. = He puts the key into the drawer.
• A kulcs a fiókban van. = The key is in the drawer.

This movement-vs-location distinction is very important in Hungarian.

Because Hungarian verbs have two main conjugation patterns:

• indefinite conjugation
• definite conjugation

Here the object is definite: a kulcsát. Because of that, Hungarian uses the definite verb form:

• tesz = indefinite
• teszi = definite, he/she puts it

So:

• A férfi egy kulcsot a fiókba tesz. = The man puts a key into a drawer.
  (indefinite object)
• A férfi a kulcsát a fiókba teszi. = The man puts his key into the drawer.
  (definite object)

This is a very common feature of Hungarian and often feels unusual to English speakers at first.

It is just the basic form.

Férfi here is the subject, and Hungarian subjects normally appear with no special ending. You can think of this as the nominative, but unlike many languages, Hungarian usually does not mark it with a separate ending.

So:

• férfi = man
• a férfi = the man

By contrast, the object kulcsát is marked, and fiókba is also marked with a case ending.

Yes, the words can be rearranged, but the meaning or emphasis may change.

This sentence is a natural neutral sentence with A férfi as the topic:

• A férfi a kulcsát a fiókba teszi.

Very roughly:

• A férfi = what we are talking about
• the rest = what happens with him

Hungarian word order is more flexible than English word order, because endings show grammatical roles. But word order is not random: it often shows topic, focus, and emphasis.

For example, moving a fiókba or a kulcsát can highlight different parts of the sentence.

So yes, the order can change, but this version is a straightforward, natural one.

It can mean several present-time ideas depending on context.

Hungarian present tense often covers:

• puts
• is putting
• sometimes even near-future meaning, depending on context

So teszi could mean:

• He puts his key into the drawer
• He is putting his key into the drawer

The situation usually makes it clear.

Hungarian does not require a separate continuous form like English is putting.

The accents in Hungarian mainly show vowel length, not stress.

Important points:

• Stress is usually on the first syllable of each word.
• á, é, í, ó, ú, ő, ű are long vowels.

In this sentence:

• férfi: the é is long
• kulcsát: the á is long
• fiókba: the ó is long
• teszi: no long vowel here

Very roughly:

• férfi ≈ FAIR-fee
• kulcsát ≈ KOOL-chaat
• fiókba ≈ fee-OAK-ba
• teszi ≈ TEH-see

Those rough English hints are imperfect, but they can help at first.

Not absolutely always, but that is the most natural reading here.

Kulcsát means his/her key, and the possessor is understood from context. In this sentence, because the subject is a férfi, most people will naturally understand it as the man puts his key into the drawer.

If Hungarian wants to make his own key especially clear or emphatic, it can say:

• a saját kulcsát = his own key

So the basic sentence already strongly suggests the man's key, but saját can make it even more explicit.

Because possession and definiteness are two different things in Hungarian.

• the possessive ending shows whose
• the article shows whether the noun phrase is definite

So:

• kulcsa = his/her key
• a kulcsa = his/her key in a definite noun phrase, often the normal form in a full sentence
• kulcsát / a kulcsát = object form

In practice, possessed nouns often appear with the definite article when they are specific, and that is exactly what happens here.

So the article is not redundant: it is doing its own job.

Yes. Tesz is a very common general verb meaning put or place, but Hungarian often has more specific alternatives.

For example:

• berakja = puts it in / inserts it
• beleteszi = puts it into it
• elteszi = can mean puts away

But teszi is perfectly correct and neutral here. It is a good basic verb to learn first.

So this sentence uses a simple, standard way to say it.