Learn Hardcore Polish: Czasem trzeba czyścić też ekran telefonu. - Sometimes you also need to clean the phone screen.

It expresses impersonal necessity: “it is necessary / one has to / you need to.” There is no grammatical subject. The understood subject is generic (one/you/we/people). Present: trzeba. Past: trzeba było (it was necessary). Future: trzeba będzie (it will be necessary). Negative: nie trzeba (it isn’t necessary).

Why is czyścić in the infinitive and not conjugated?

After trzeba, Polish uses the infinitive. So you say trzeba czyścić (“one needs to clean”), not “trzeba czyści.” The infinitive is the standard complement of impersonal necessity here.

Why imperfective czyścić and not perfective wyczyścić?

Imperfective czyścić fits habitual or repeated actions, which matches czasem (“sometimes”). If you want a one‑off, result‑focused necessity, use perfective: Trzeba wyczyścić ekran telefonu (“It’s necessary to get the phone screen cleaned [this time]”). Your sentence with czyścić reads as a general habit: sometimes it’s necessary to clean it.

What does też mean, and why is it placed there?

Też means “also/too.” In Czasem trzeba czyścić też ekran telefonu, putting też right before ekran telefonu highlights that the screen is an additional thing that needs cleaning (e.g., besides the case or camera lens). Polish allows flexible placement, but keep też close to what is being added for clarity.

Would Czasem też trzeba czyścić ekran telefonu be different in meaning?

Slightly. Czasem też trzeba… puts “also” earlier, which tends to add the whole necessity to a list of necessities. Compare:

Czasem też trzeba czyścić ekran telefonu = sometimes you also need to (among other needed tasks).
Czasem trzeba czyścić też ekran telefonu = sometimes you need to clean the screen, too (among other things to clean). Both are correct; the nuance is about what the “also” attaches to.

Why is it ekran telefonu and not ekran telefon?

Polish expresses “X of Y” with Y in the genitive case. So “screen of the phone” is ekran telefonu (genitive singular of “telefon” = telefonu). The direct object here is ekran (accusative = same as nominative for inanimate masculine), and telefonu depends on the noun ekran.

Why isn’t it ekranu here?

Because in an affirmative sentence with a verb that normally takes an accusative object, ekran stays accusative: czyścić ekran. It becomes genitive in certain contexts, most notably under negation or with verbs that govern the genitive. For example:

Negation: Nie trzeba czyścić ekranu telefonu (“It isn’t necessary to clean the phone’s screen”).
Genitive‑taking verb: Dotykam ekranu (“I’m touching the screen”).

Can I replace ekran telefonu with a pronoun?

Yes. Since ekran is masculine inanimate, use go (unstressed clitic) for the object:

Czasem trzeba też go czyścić.
Czasem trzeba go też czyścić. Both are natural; keep go early in the clause and avoid stressing it.

Could I say musisz instead of trzeba?

You can, but it changes the tone and the subject. Czasem musisz czyścić ekran telefonu directly addresses “you” (singular) and is stronger (“you must”). Trzeba is impersonal and more general. Other options:

Powinno się czyścić… (“one should” – softer, impersonal)
Należy czyścić… (formal “it is recommended/required to”)

Are czasem and czasami interchangeable?

Yes. Czasem and czasami both mean “sometimes”; czasem is a bit shorter and very common. A more formal synonym is niekiedy.

Is również or także a good replacement for też?

Usually yes. Również is a bit more formal; także also means “also,” but don’t confuse it with the two‑word tak że (“so/therefore”). All three fit: … trzeba również/także czyścić… The choice affects register more than meaning.

Is czyścić się correct here?

No. Czyścić się would mean “to clean itself/to get clean,” which doesn’t fit. Use the active transitive verb: czyścić (coś), or a passive if needed: Ekran jest czyszczony (“The screen is being cleaned”).

Should I use ekran or wyświetlacz for “screen”?

For everyday talk about cleaning a phone’s screen, use ekran. Wyświetlacz (“display module”) is more technical and common in hardware contexts. Both are understandable, but ekran is the default here.

How do I pronounce the tricky parts?

trzeba ≈ “CHEH-bah” (the initial sound like “ch” in “church,” but a bit retroflex)
czyścić ≈ “CHISH-chich” (soft “ś/ć” are like “sh/ch” but palatal)
też ≈ “tesh” (voiced “ż/ż” sound at the end) Polish stress is on the second-to-last syllable: te-le-FO-nu in telefonu.

Can I move czasem to a different place?

Yes. All of these are fine, with subtle shifts in emphasis:

Czasem trzeba czyścić też ekran telefonu.
Trzeba czasem czyścić też ekran telefonu.
Czasem też trzeba czyścić ekran telefonu. Beginning placement is very common and neutral.

How would I say this in the past or future?

Use the periphrastic forms of trzeba:

Past: Czasem trzeba było czyścić też ekran telefonu. (“Sometimes it was necessary to clean the phone screen, too.”)
Future: Czasem trzeba będzie czyścić też ekran telefonu. (“Sometimes it will be necessary…”)

How do I negate the sentence correctly?

Negate the necessity or the action:

Negating necessity: Czasem nie trzeba czyścić ekranu telefonu. (“Sometimes it isn’t necessary to clean the phone’s screen.”) Note the object becomes genitive: ekranu.
Negating the action (less common with impersonal necessity): Trzeba nie czyścić ekranu telefonu is possible in specific contrastive contexts but sounds odd in isolation; the first version is the natural choice.