Moja przyjaciółka narzeka, że napisy znikają za szybko.

A word-by-word breakdown:

• moja = my
• przyjaciółka = female friend
• narzeka = complains / is complaining
• że = that
• napisy = subtitles / captions / text on screen (depending on context)
• znikają = disappear / are disappearing
• za szybko = too quickly / too fast

So the whole sentence means something like: My friend complains that the subtitles disappear too quickly.

Because przyjaciółka is a feminine noun, and the possessive adjective my has to agree with it in gender.

So:

• mój = my, for a masculine singular noun
• moja = my, for a feminine singular noun
• moje = my, for a neuter singular noun

Examples:

• mój brat = my brother
• moja siostra = my sister
• moje dziecko = my child

Since przyjaciółka is feminine, you need moja.

Przyjaciółka specifically means a female friend.

Polish distinguishes between:

• przyjaciel = male friend
• przyjaciółka = female friend

English usually just says friend, unless gender matters.

Be careful: in some contexts, przyjaciółka can sometimes sound quite close or personal, because przyjaciel / przyjaciółka often suggests a real friend, not just an acquaintance. For a more casual friend/person I know, Polish also often uses kolega / koleżanka.

Narzeka is the 3rd person singular present tense form of narzekać (to complain).

Because the subject is moja przyjaciółka (my friend), the verb must match she:

• ja narzekam = I complain
• ty narzekasz = you complain
• on / ona narzeka = he / she complains

So:

• Moja przyjaciółka narzeka = My friend complains / is complaining

Polish present tense often covers both the English simple present and present continuous, depending on context.

In Polish, a comma is normally placed before że when it introduces a subordinate clause.

So in:

• Moja przyjaciółka narzeka, że napisy znikają za szybko

the part after że is a clause: that the subtitles disappear too quickly.

This comma is standard in Polish punctuation. English sometimes feels less strict to learners, but in Polish this comma is expected.

Że means that and introduces a subordinate clause.

So:

• narzeka, że... = complains that...

It links the main idea to the content of the complaint.

Compare:

• Myślę, że... = I think that...
• Wiem, że... = I know that...
• Mówi, że... = He/She says that...

So here, że napisy znikają za szybko explains what she is complaining about.

Napisy is the plural form of napis.

Depending on context, napis/napisy can mean:

• inscription / writing
• text
• captions
• subtitles

In this sentence, the natural meaning is subtitles or on-screen captions.

Because napisy is plural, the verb also has to be plural:

• napisy znikają = the subtitles disappear

Znikają is the 3rd person plural present tense form of znikać (to disappear).

The subject is napisy (subtitles), which is plural, so the verb must also be plural.

Present tense forms of znikać include:

• ja znikam = I disappear
• ty znikasz = you disappear
• on / ona znika = he / she disappears
• my znikamy = we disappear
• wy znikacie = you all disappear
• oni / one znikają = they disappear

So:

• napisy znikają = the subtitles disappear / are disappearing

Here za means too.

So:

• szybko = quickly / fast
• za szybko = too quickly / too fast

This is a very common Polish pattern:

• za drogo = too expensive
• za późno = too late
• za wcześnie = too early
• za wolno = too slowly

So napisy znikają za szybko means the subtitles do not stay long enough on the screen.

Yes, Polish word order is more flexible than English, although some versions sound more natural than others.

The original sentence:

• Moja przyjaciółka narzeka, że napisy znikają za szybko.

is neutral and natural.

You could also hear:

• Moja przyjaciółka narzeka, że za szybko znikają napisy.
• Napisy znikają za szybko, mówi moja przyjaciółka.

The meaning stays similar, but the emphasis changes.

In general, the original order is the safest choice for learners.

Yes. Polish present tense often corresponds to both:

• complains
• is complaining

So narzeka can mean either one, depending on context.

The same is true for znikają:

• they disappear
• they are disappearing

Polish does not have a separate tense formed like English am/is/are + -ing. Instead, the plain present tense often covers both meanings.

Yes. Both narzekać and znikać are imperfective verbs.

That matters because imperfective verbs are typically used for:

• ongoing actions
• repeated actions
• general situations
• present tense statements

That fits this sentence well:

• she is complaining / tends to complain
• the subtitles disappear too quickly

The perfective counterpart of znikać is zniknąć (to disappear once / to vanish completely), but perfective verbs normally do not have a regular present tense meaning. Their present forms usually refer to the future.

So for a general present statement like this, znikają from znikać is exactly what you want.

A rough guide:

• przyjaciółka ≈ pshi-ya-CHOOW-ka
• znikają ≈ znee-ka-YON

A few useful pronunciation notes:

• rz usually sounds like the s in measure or zh
• ó sounds like u
• ł sounds like English w
• ą is a nasal vowel, often sounding roughly like on / om depending on position
• Polish stress usually falls on the second-to-last syllable

So:

• przy-ja-CIÓŁ-ka
• zni-KA-ją

The exact sounds are a bit different from English, but those approximations can help at first.