Learn Hardcore Polish: Który rozmiar wolisz?

Który = which (masculine singular; here matching the noun)
rozmiar = size (masculine inanimate; here functioning as the direct object)
wolisz = you prefer (2nd person singular present of woleć “to prefer”) Polish doesn’t need a helper like “do” for questions, so there’s no equivalent of “do you.”

Why is it który and not jaki?

który = “which (one)” when choosing from a specific, known set (e.g., S/M/L on a label or options in front of you).
jaki = “what (kind of)”/“what” when the set isn’t specified or you’re asking more generally. Both can appear in casual speech with clothing sizes. Examples:
Który rozmiar wolisz – S czy M? (which of these)
Jaki rozmiar wolisz? (what size in general)

What case is rozmiar in here?

Accusative. The verb woleć takes a direct object in the accusative. Since rozmiar is masculine inanimate, its accusative form looks the same as nominative: rozmiar. You see a change with masculine animate nouns: e.g., “Which dog do you prefer?” → Którego psa wolisz?

Does który have to agree with the noun?

Yes—by gender, number, and case.

Masculine singular (inanimate): Który rozmiar wolisz?
Feminine singular: Którą koszulkę wolisz?
Neuter singular: Które danie wolisz?
Plural (non-masculine personal): Które rozmiary wolisz?

What form is wolisz and how do you conjugate woleć?

Wolisz = 2nd person singular present. Present-tense conjugation:

ja wolę
ty wolisz
on/ona/ono woli
my wolimy
wy wolicie
oni/one wolą Past (examples): ja wolałem/wolałam, ty wolałeś/wolałaś, on wolał, ona wolała.

How do I say this politely/formally?

To one man/woman (formal): Który rozmiar pan/pani woli?
To a group (formal): Który rozmiar państwo wolą? In writing, Pan/Pani/Państwo are often capitalized out of politeness. Don’t use ty in formal speech.

Can I change the word order?

Wh-words like który normally come first in neutral questions: Który rozmiar wolisz?
Forms like Wolisz który rozmiar? are possible in very specific, echo-like contexts (“You prefer which size?”) but sound marked or less natural. Stick to the original order.

How do I handle plural “sizes” or “you (plural)”?

Plural noun: Które rozmiary wolisz? (“Which sizes do you prefer?” to one person)
Plural “you”: Który rozmiar wolicie? / Które rozmiary wolicie? (“you all”)
Formal plural: Który rozmiar państwo wolą?

How do I pronounce the tricky bits?

Kt in Który: pronounce both consonants together, no vowel between (k+t).
ó = the sound of u (like “oo” in “boot”): Który → “KTOO-ri.”
w = “v” in English: wolisz → “VO-lish.”
sz = “sh”: the ending of wolisz is “-sh.” Stress is on the second-to-last syllable: KTÓ-ry, VO-lish, ROZ-miar.

Can I use lubić (“to like”) instead of woleć?

Generally no. Woleć = “to prefer,” i.e., choose one option over another. Lubić = “to like.”

Natural: Który rozmiar wolisz?
Less natural: Który rozmiar lubisz?
If you mean “Which size do you like (the look of)?”, you can say: Który rozmiar bardziej ci się podoba?

Can I drop the noun and just say “Which (one) do you prefer?”

Yes, if context makes it clear: Który wolisz?
It stays który (not którego) because the understood noun rozmiar is masculine inanimate, and its accusative matches the nominative. With masculine animate nouns, you’d see którego: e.g., Którego wolisz? (meaning “Which [man/dog/etc.] do you prefer?”).

How would I answer naturally?

Wolę M. / Wolę rozmiar M.
Wolę średni. (medium)
Wolę mniejszy/większy. Colloquially for letter sizes: emkę (M), eskę (S), elkę (L) in the accusative: Wolę emkę/eskę/elkę.

Is Który rozmiar wolisz? the most natural phrasing?

It’s natural when a set is visible/specific. If you’re asking more generally (without a visible set), many speakers would use Jaki rozmiar wolisz? Both are acceptable; context decides.

Any nuance for “prefer A to B” in Polish?

Common, natural patterns:

Wolę A niż B.
Wolę A, a nie B. You’ll also hear: Wolę A od B, which is widely used in speech. For polite hedging: Wolałbym/wolałabym A.

Is rozmiar always the right word for “size”?

For clothes, rozmiar is standard. For shoes, people also say numer (buta):

Jaki masz rozmiar? (clothes)
Jaki masz numer buta? or Jaki masz rozmiar buta? (shoes)