Interrogative pronouns

as well as relative, demonstrative, indefinite, negative and generalizing

Keep in mind, this is not a complete list of pronouns. We will address the following separately:
personal pronouns (ja, ty, ona...), possessive pronouns (mój, twój...), and the reflexive and reciprocal pronoun (się).

The following cases - interrogative (which also act as relative), demonstrative, indefinite, negative and generalizing - have been put together so that you can see how they relate to each other and notice the pattern of formation, which is quite simple:

interrogative, relative	demonstrative	indefinite	negative	generalizing
kto? who? example Kto dzwonił? Who called?	ten the one example Ten, kto to zrobił, jest prawdziwym artystą. The one who did this is a true artist.	ktoś someone example Ktoś mnie obserwuje. Someone is watching me.	nikt no one example Nikt nie wie, co się stało. Nobody knows what happened.	każdy + singular wszyscy + plural each all example Każdy idzie na koncert. Wszyscy idą na koncert. Everyone is going to the concert.
co? what? example Co dzisiaj zamawiamy? What are we ordering today?	to it, this example Powiedziałam to, żeby sprawdzić, jak zareagujesz. I said this to see how you would react. Notice that to as "the thing I'm pointing at" has one form regardless of the gender of the thing: To jest mężczyzna (It's a man). To jest kobieta (It's a woman). To jest dziecko (It's a child). etc. The forms will be different when this object - and not "it" - is the subject of the sentence: Ten mężczyzna jest zmęczony. Ta kobieta jest zmęczona. To dziecko jest zmęczone. - but then it's technically another pronoun, see the cell below [ten, ta, to, ci, te].	coś something example Widzę coś na stole. I see something on the table.	nic nothing example Nie mam nic przeciw… I have nothing against…	wszystko everything example Zrobię dla ciebie wszystko. I'll do everything for you.
czyj? czyja? czyje? czyi? czyje? whose? example Czyja to wina? Whose fault is that?	—	czyjś, czyjaś, czyjeś czyiś, czyjeś someone's example Czyjś łokieć dotknął moich pleców. Somebody's elbow touched my back.	niczyj, niczyja, niczyje niczyi, niczyje nobody's example Niczyje życie nie może być takie idealne. Nobody's life can be this perfect.	—
jaki? jaka? jakie? jacy? jakie? what [kind of]? example Wie pan z jaką prędkością jechał? Do you know what speed you were driving at?	taki, taka, takie tacy, takie such example Nie patrz na mnie w taki sposób. Don't look at me in such way.	jakiś, jakaś, jakieś jacyś, jakieś some [kind of] example Może macie jakieś pytania. Perhaps you have some questions.	żaden, żadna, żadne żadni, żadne none example Nie zrobię tego za żadne pieniądze świata. I won't do it. For no money in the world.	każdy, każda, każde –, każde each, every wszyscy, wszystkie* all example Każdy dzień to nowa szansa. Every day is a new chance. Lubię wszystkie psy. I like all dogs. * The form of the pronoun "każdy" for the masculine-personal plural (oni), although technically possible, is considered incorrect and is not used.
który? która? które? którzy? które? which? example Któremu czasopismu literackiemu zaufać? Which literary journal should we trust?	ten, ta, to ci, te this; these tamten, tamta, tamto tamci, tamte that; those example Dlaczego kupiłeś ten dom, a nie tamten? Why’d you buy this house, and not that one?	któryś, któraś, któreś którzyś, któreś some [of], one [of] example Podobno któryś z was ma doświadczenie z końmi. Allegedly one of you has horse experience.
gdzie? where? example Gdzie mieszkasz? Where do you live?	tu / tutaj [to] here tam [to] there	gdzieś somewhere	nigdzie nowhere	wszędzie [to] everywhere
dokąd? [to] where? example Dokąd idziesz? Where are you going? * Nowadays, in colloquial language, it gets more common to use gdzie (formerly used to indicate a static location) instead of dokąd (used to indicate direction). So, you can also say: Gdzie idziesz?	tu / tutaj [to] here tam [to] there	dokądś [to] somewhere	donikąd [to] nowhere	wszędzie [to] everywhere
skąd? from where? example Skąd pochodzisz? Where do you come from?	stąd from here stamtąd from there	skądś from somewhere	znikąd from nowhere	zewsząd from everywhere
kiedy? when? *gdy only as relative pronoun	wtedy then	kiedyś sometime, someday	nigdy never	zawsze always
jak? how?	tak so, like this	jakoś somehow	w żaden sposób nijak (informal) in no way	wszak in modern Polish: after all*!
ile? how much? / how many? / [for] how long? example Ile to kosztuje? How much is it? Ile masz psów? How many dogs do you have? Ile muszę czekać? How long do I have to wait?	tyle this much / this many	ileś some [amount of]	—	—

What else?

dlaczego

I decided not to include the interrogative pronouns dlaczego and czemu in the table, because we do not derive negative or generalizing pronouns from them. However, we can still compare the interrogative, demonstrative and indefinite forms, as they still follow the same pattern:

dlaczego? / czemu? – dlatego – dlaczegoś
why? – that's why – for some reason

By the way: you may notice that dlaczego is essentially derived from the interrogative pronoun co, declined in the genitive case and combined with the preposition dla. Both the combined and separated spellings exist, although their meanings are a bit different:

Dla czego? For what?
Musisz mieć coś, dla czego żyjesz.
You have to have something you live for.

Dlaczego? Why?
Dlaczego żyjesz w ten sposób?
Why do you live this way?

The form czemu (more colloquial) is also, in fact, a form of the pronoun co, but declined in the dative case (literally: "to what" or "for what").

-kolwiek

I also decided not to include the indefinite pronoun variant with the suffix -kolwiek, which corresponds roughly to English -ever or any-. The forms would look as follows:

ktokolwiek (whoever), cokolwiek (whatever), jakikolwiek (whatever, adjective), którykolwiek (whichever, any one of), gdziekolwiek (wherever, anywhere), dokądkolwiek (to anywhere), skądkolwiek (from anywhere), kiedykolwiek (whenever, at any time), jakkolwiek (however, anyhow), ilekolwiek (however much).

To illustrate the meaning of this suffix, let's compare the indefinite pronouns ktoś and ktokolwiek:

Ktoś puka do drzwi.
Someone (one specific person) is knocking on the door.
Czy ktokolwiek pukał dzisiaj do drzwi?
Did anyone knock on the door today?
Ktokolwiek pukał do drzwi, nie powinien był cię niepokoić.
Whoever knocked on the door should not have disturbed you.

Nowadays, pronouns with -kolwiek are used less frequently and are often replaced by pronouns with -ś. The sentences above can be transformed using ktoś:

Czy ktoś pukał dzisiaj do drzwi?
Did someone knock on the door today?

Ktoś, kto pukał do drzwi, nie powinien był cię niepokoić. | Kto by nie pukał do drzwi, nie powinien był cię niepokoić.
The person who knocked on the door should not have disturbed you. | Whoever knocked [very literally: who wouldn't knock] on the door should not have disturbed you.

którędy

It was not included in the table to avoid a mess and confusion with archaic forms which remained as demonstratives only and were otherwise replaced by gdzie derivatives (nigdzie, wszędzie), but it's still one of the interrogative pronouns: którędy - which way, by which route (referring to movement in space).

interrogative	demonstrative	indefinite	negative	generalizing
którędy, *kędy (archaic) which way	tędy, tamtędy this way, that way	którędyś, *kędyś (archaic) którędykolwiek by some route, whichever way	nigdzie, *nikędy (archaic) nowhere, by no route	wszędzie, *wszędy (archaic) everywhere

Examples:

Woda deszczowa spływa którędyś, ale nie wiem, którędy dokładnie.
The rainwater is flowing down somewhere, but I don't know exactly which way.

Poszedłem tędy, a oni tamtędy.
I went this way, and they went that way.

Możesz chodzić którędykolwiek, to bezpieczna okolica.
You can walk whichever way you like; it's a safe area.

Declension

Prerequisites: knowledge of the functions and usage of grammatical cases.

Pronouns can decline for grammatical cases. For those presented in the tables above, it looks like this:

kto, co (and their corresponding demonstrative, indefinite, negative, and generalizing pronouns) - decline only in the singular and, as you can see below, they do so in a way resembling the masculine pattern. I've placed the full declension of these pronouns in a column together with the case names.
czyj, jaki, który (and their corresponding demonstrative, indefinite, negative, and generalizing pronouns, including żaden, każdy, wszyscy/wszystkie) - decline for all genders and numbers.
gdzie, skąd, dokąd, którędy, kiedy, jak, dlaczego – these are adverbial pronouns, so, they do not decline for case at all.
ile (as well as demonstrative tyle and indefinite ileś) - declines accordingly to the pattern for numerals from 5 upwards nominative: ile
genitive: ilu
dative: ilu
accusative: ilu (masculine-personal - oni), ile (one)
instrumental: iloma
locative: ilu
.

Therefore, here you have the pattern of adjectival endings in grammatical cases, as it's the only one you will need here:

	singular			plural
	masculine	neuter	feminine	masculine-personal (oni)	non-masculine-personal (one)
nominative kto? co?	-y / -i * The ending -i goes after a stem ending in -k or -g. In the case of our pronouns this will be jaki and taki. except for czyj and żaden	-e	-a	-i / -y * Careful: Here, the ending -i is standard, while -y goes after the stem that, in singular form, ends in -c, -cz or -ż and as a result of alternations: -cy → -cy (stays the same) -czy → -czy (stays the same) -ży → -ży (stays the same) -ki → -cy -gi → -dzy -ry → -rzy In the case of our pronouns this will be: jaki → jacy taki → tacy który → którzy wszystki (archaic) → wszyscy.	-e
genitive kogo? czego?	-ego		-ej	-ych / -ich * The ending -ich goes after a stem ending in -k or -g. In the case of our pronouns this will be jakich, takich and wszystkich.
dative komu? czemu?	-emu		-ej	-ym / -im * The ending -im goes after a stem ending in -k or -g. In the case of our pronouns this will be jakim, takim and wszystkim.
accusative kogo? co?	-ego (animate) -y / -i (inanimate) * The ending -i goes after a stem ending in -k or -g. In the case of our pronouns this will be jaki and taki.	-e	-ą	-ych / -ich * The ending -ich goes after a stem ending in -k or -g. In the case of our pronouns this will be jakich, takich and wszystkich.	-e
instrumental kim? czym?	-ym / -im * The ending -im goes after a stem ending in -k or -g. In the case of our pronouns this will be jakim and takim.		-ą	-ymi / -imi * The ending -imi goes after a stem ending in -k or -g. In the case of our pronouns this will be jakimi, takimi and wszystkimi.
locative kim? czym?	-ym / -im * The ending -im goes after a stem ending in -k or -g. In the case of our pronouns this will be jakim and takim.		-ej	-ych / -ich * The ending -ich goes after a stem ending in -k or -g. In the case of our pronouns this will be jakich, takich and wszystkich.

If you're unsure what are the alternative endings -y / -i about, hover the cursor over the asterisks.
Additionally, similar logic works for the endings -e and -ej in the neuter, feminine and non-masculine-personal genders. If they follow a verb stem ending in -k or -g, they will take the forms -ie and -iej, respectively.
Compare: który → które, której, but: jaki → jakie, jakiej.

I suggest to put aside memorizing these endings without context for now and to try the following exercises. If you've studied grammatical cases before, chances are you'll choose the correct pronoun form based on its similarity to the adjectives in the appropriate cases. In case of doubts or errors, check the table.

As was mentioned, not only interrogative pronouns decline for cases, but also their demonstrative, indefinite, negative, and generalizing counterparts.
Let's compare the nominative co and its analogues with the genitive czego and its analogues:

co	to	coś	nic	wszystko
czego	tego	czegoś	niczego	wszystkiego

As you can see, the pronoun markers remain the same. For a better overview, let's also compare the nominative masculine jaki and its analogues with, say, the feminine accusative jakiej and its analogues:

jaki	taki	jakiś	żaden	każdy
jakiej	takiej	jakiejś	żadnej	każdej

The number of pronouns with adjectival inflection, multiplied by the number of Polish grammatical genders and then by the number of grammatical cases, gives about a fuck-ton of different forms. But hopefully that at this point, you don't see them as thousands of separate words to learn one by one (or to spit on them all together), but as words you can assemble yourself, like building blocks, from pronoun stems you're familiar with and morphemes that modify their meaning depending on what you want to convey.

In the exercise below we have a mix - inflected and uninflected pronouns:

As for pronoun forms - that's basically it, the hardest part is over.

🎉 🎉 🎉

There are also a few syntactic issues that, I guess, could be clarified in this chapter. It happens that students learning Polish use calques of English syntax, but it doesn't always work, so let's address the moments where this can lead to confusion: the use of relative pronouns, forming questions with prepositions and interrogative pronouns, and double negation.

Relative pronouns

Let's consider how the following phrases would sound in Polish:

She wanted to be somewhere no one knew her. Chciała być gdzieś, gdzie nikt jej nie zna.
It's something I've read about. To coś, o czym czytałem.
I need someone I can turn the material over to. Potrzebuję kogoś, komu przekażę materiały.
The soup was what we expected from a charity. Zupa była taka, jakiej spodziewaliśmy się po instytucji dobroczynnej.