A gyógyszertárban gyógyszert kérek, mert fáj a fejem és a torkom.

-ban/-ben is the inessive case, meaning in/inside something.
So a gyógyszertárban = in the pharmacy.

Which one you use depends on vowel harmony:

• -ban after back vowels (a, á, o, ó, u, ú) → gyógyszertárban
• -ben after front vowels (e, é, i, í, ö, ő, ü, ű) → e.g. a boltban vs a pékségben

Hungarian often uses the definite article a/az in places where English might use the, a, or even no article, especially with locations used generically.

So A gyógyszertárban can mean:

• In the pharmacy (a specific one in context), or
• At the pharmacy / In a pharmacy (generic situation)

It’s very normal to start a sentence this way in Hungarian.

They are both the (definite article).

• a is used before consonant sounds: a gyógyszertár
• az is used before vowel sounds: az orvos, az iskola

-t marks the accusative case, i.e. the direct object of the verb.

• gyógyszer = medicine (base form)
• gyógyszert = (some) medicine (as the thing being requested)

So gyógyszert kérek = I’m asking for medicine / I’d like medicine.

Both are possible, but they differ in meaning:

• Gyógyszert kérek. = I’d like some medicine (unspecific / “medicine in general”)
• Egy gyógyszert kérek. = I’d like a medicine / one medicine (more like “one item”)

In a pharmacy, the unspecific gyógyszert kérek is very natural if you haven’t specified which exact product yet.

Hungarian has two verb conjugations:

• indefinite (when the object is not specific/definite)
• definite (when the object is specific/definite)

Here, gyógyszert is not a specific, identified medicine, so you use the indefinite form:

• (Én) kérek = I ask / I’d like

You’d use kérem if the object is definite, e.g.:

• A gyógyszert kérem. = I’d like the medicine (a specific one already identified)
• Azt kérem. = That one, please.

mert means because, and it introduces a reason clause.

The word order after mert is fairly flexible, but Hungarian commonly keeps the verb early or in a natural emphasis pattern:

• ..., mert fáj a fejem és a torkom. = ..., because my head and throat hurt.

You could also hear slightly different emphasis:

• ..., mert a fejem és a torkom fáj. (more emphasis on which parts)

That’s the normal Hungarian structure for pain:

• fáj = hurts
• the thing that hurts is the grammatical subject

And possession is expressed with a possessive ending:

• fej = head
• fejem = my head
• a fejem = literally the my head, but idiomatically just my head

So fáj a fejem = my head hurts.

With body parts (and many possessed nouns), Hungarian very often uses the definite article a/az:

• fáj a fejem (most common)
• fáj a torkom

Dropping the article can sound more like a headline/telegraphic style or a special emphasis, but the standard everyday phrasing includes a.

You can repeat the article for clarity and natural rhythm:

• a fejem és a torkom = my head and my throat

In casual speech, the second article is sometimes omitted:

• a fejem és torkom (possible, but less “carefully” phrased)

Repeating a is a safe, standard choice for learners.

Key sounds:

• gy ≈ like the d in British duke / a “soft d” (not exactly, but close)
• sz = s (so gyógyszer has an s sound at the end)
• s = sh (not present here, but useful contrast)
• á is a long a (as in father, but longer)

Rough guide:

• gyógyszer ≈ dyoog-ser
• gyógyszertárban ≈ dyoog-ser-taar-ban