Learn Hardcore Hungarian: Szerintem ez a történet érdekes, de hosszú. - In my opinion this story is interesting but long.

The subject “I” is understood from the ending -em, so you don’t need to say én or an explicit verb like gondolom (I think). You can say:

Én úgy gondolom, hogy ez a történet érdekes.
Azt hiszem, ez a történet érdekes.

but Szerintem… is the most common, short, natural way.

Why is there no word for is in Szerintem ez a történet érdekes, de hosszú?

Hungarian usually drops the verb “to be” (van) in the present tense, 3rd person, when it simply links a noun and an adjective or noun:

Ez a történet érdekes.
literally: This story interesting.
meaning: This story is interesting.

So you must not say:

✗ Ez a történet van érdekes. (wrong here)

You only use van in the present:

In existential sentences (there is / there are):
- Van egy könyvem. – I have a book (literally: There is a book of-mine.)
For emphasis or contrast in certain patterns.
In other persons or tenses:
- Én vagyok fáradt. – I am tired.
- Ez a történet hosszú volt. – This story was long.

In your sentence, érdekes and hosszú are simple predicates in the present, so no “is” word is needed.

Why do we say ez a történet and not just ez történet for “this story”?

In Hungarian, when a demonstrative like ez (this) or az (that) directly modifies a noun, you almost always use the definite article a/az as well:

ez a történet – this story
az a könyv – that book
ez a ház – this house

So the pattern is:

ez/az + a/az + noun

To an English speaker it may look like “this the story”, but in Hungarian this is completely normal and required.

Without the article:

ez történet sounds wrong or, at best, very strange and ungrammatical in normal speech.

Can I leave out szerintem and still say Ez a történet érdekes, de hosszú?

Yes.

Ez a történet érdekes, de hosszú.
= This story is interesting but long.

This is now a more objective-sounding statement, like you’re just describing a fact.

With szerintem:

Szerintem ez a történet érdekes, de hosszú.
= In my opinion, this story is interesting but long.

Now you clearly mark it as your personal opinion. Both are grammatical; the difference is in how subjective it sounds.

Where else can I put szerintem in the sentence, and does the meaning change?

You can move szerintem around a bit. All of these are grammatical:

Szerintem ez a történet érdekes, de hosszú.
Ez a történet szerintem érdekes, de hosszú.
Ez a történet érdekes, szerintem, de hosszú. (spoken, with pauses)

The basic meaning “in my opinion” stays the same, but:

Version 1 (at the beginning) is the most common and neutral.
Version 2 can slightly highlight “this story” as the thing you’re giving your opinion about.
Version 3 sounds more like an afterthought (“…is interesting, I think, but long”).

In practice, use Szerintem… at the start most of the time; it’s natural and safe.

Do the adjectives érdekes and hosszú change form to agree with történet?

Hungarian adjectives don’t change for gender (Hungarian has no grammatical gender), but they do show plural agreement in certain positions.

In your sentence, történet is singular, so:

Ez a történet érdekes, de hosszú.
(no extra endings on érdekes, hosszú)

If the subject is plural, and the adjective is in predicate position (after the noun, with an invisible “is”), you usually add a plural ending -ak / -ek / -ok:

Ezek a történetek érdekesek, de hosszúak.
= These stories are interesting but long.

But if the adjective is in front of the noun (attributive), it usually stays unmarked, even in the plural:

Érdekes történetek. – Interesting stories. (no -ek on érdekes)

So:

predicate (after noun) + plural → érdekesek, hosszúak
attributive (before noun) + plural → érdekes történetek, hosszú történetek

What is the role of the comma before de, and is it always needed?

In your sentence:

Szerintem ez a történet érdekes, de hosszú.

the comma before de marks a contrast: interesting, but long.

Hungarian normally uses a comma before “de” when:

it connects two parts that could stand alone as separate statements, or
it clearly contrasts two elements (érdekes vs hosszú).

In short, in this sentence the comma is standard and recommended.
In very short or less contrasting phrases, you might sometimes see no comma, but the safe rule for learners is:

If de means but and clearly contrasts two parts → put a comma before it.

Is de always translated as “but”? Are there alternatives?

De most commonly means but:

Érdekes, de hosszú. – Interesting but long.

There are other contrastive words in Hungarian:

viszont – however / on the other hand
- Érdekes, viszont hosszú.
azonban – however / nevertheless
- Érdekes, azonban hosszú.

They’re a bit more formal or stylistically marked.
For everyday “but”, de is the default choice and is exactly right in your sentence.

What does történet mean exactly, and how is it different from történelem or sztori?

történet
= story, tale, narrative (a specific story, like one you read or tell)
e.g. Ez a történet érdekes. – This story is interesting.
történelem
= history (the subject; the past of nations, etc.)
e.g. Szeretem a történelmet. – I like history.
sztori (from English story)
= informal, colloquial story
e.g. Ez a sztori vicces. – This story is funny.

In your sentence, történet is the normal, neutral word.

How do you pronounce történet, and what do the accented vowels ő and é indicate?

Történet is pronounced approximately:

tőr-té-net
[ˈtøːrteːnɛt]

Key points:

ő – a long, front, rounded vowel.
It’s like a longer version of German ö or the vowel in French peu.
é – a long “é” sound, close to “ay” in English “say”, but purer (no glide).
A single e is short, like the e in “bet”.

So you have two long vowels (ő, é) and one short final e. Vowel length (short vs long) is phonemic in Hungarian: it can change the meaning of words, so it matters.

How would I make this sentence plural, like “In my opinion, these stories are interesting but long”?

You need to make the demonstrative, the noun, and the predicate adjectives all plural:

Szerintem ezek a történetek érdekesek, de hosszúak.

Breakdown:

ezek – these (plural of ez)
a történetek – the stories (történet → történetek)
érdekesek – plural predicate form of érdekes
hosszúak – plural predicate form of hosszú

So singular:

Ez a történet érdekes, de hosszú.

plural:

Ezek a történetek érdekesek, de hosszúak.

How would I say “In my opinion, this story is not interesting but long” in Hungarian?

You need to use nem for “not” and hanem for “but (rather)” after a negation:

Szerintem ez a történet nem érdekes, hanem hosszú.

Explanation:

nem érdekes – not interesting
hanem hosszú – but (rather) long

In Hungarian:

de = but in general contrast.
hanem = but rather / but instead after a negation.

So:

Nem érdekes, hanem unalmas. – It’s not interesting but (rather) boring.