Pronouns

General usage:
Basically a pronoun replaces a noun. All pronouns, but not the reflexive pronouns, decline for gender, number and case of the noun which they replace. Some pronouns are identical to their adjective counterpart.
 

Personal pronouns:
In Polish, you have three types of personal pronouns: ordinary, emphatic and prepositional.

Ordinary:
These are used when there is no need for emphasis and if the pronoun does not follow a preposition.
The pronouns ty and wy are sometimes used with a personal name to attract attention.
The pronouns mię, mi, cię, ci, go and mu cannot start the sentence nor can they carry the sentence stress.
Usually you omit the nominative case personal pronoun, except in cases where this may lead to misinterpretations since there is a verb beginning like a pronoun. myjemy and jemy for example - both have totally different meanings.
 

	I	you (singular)	he	she	it	we	you (plural)	they (men)	they (non-men)
Nominative	ja	ty	on	ona	ono	my	wy	oni	one
Vocative	ja	ty				my	wy
Accusative	mię	cię	go	ją	je	nas	was	ich	je
Genitive	mię	cię	go	jej	go	nas	was	ich	ich
Instrumental	mną	tobą	nim	nią	nim	nami	wami	nimi	nimi
Dative	mi	ci	mu	jej	mu	nam	wam	im	im

Note: There is no locative case for ordinary personal pronouns.

You use ty and wy only for persons you know well (friends, family-members, ...). In all other cases you use the formal form namely the nouns pan (for a man), pani (for a woman), panowie (for men), panie (for women), państwo (for mixed groups) and panna (for young woman) and panienka (for young women). However the last two forms can be in some case politically incorrect, so be careful with them.
Often you use Pan, Pani or Panna before the first names to imply familiarity.
Please note: Pan, Pani and Panna should have a capital "P", esp. in letters.

Emphatic:
As the name states, you use this form if you need to put emphases on the pronoun. However, there is no emphatic form for all ordinary personal pronouns. If none does exist, you use the ordinary form instead.
 

	I	you (singular)	he	it
Accusative	mnie	ciebie	jego
Genitive	mnie	ciebie	jego	jego
Dative	mnie	tobie	jemu	jemu

Prepositional:
This form is used after a preposition.
 

	I	you (singular)	he	she	it	we	you (plural)	they (men)	they (non-men)
Accusative	mnie	ciebie	niego	nią	nie	nas	was	nich	nie
Genitive	mnie	ciebie	niego	niej	niego	nas	was	nich	nich
Instrumental	mną	tobą	nim	nią	nim	nami	wami	nimi	nimi
Dative	mnie	tobie	niemu	niej	niemu	nam	wam	nim	nim

Reflexive pronouns:
These are used when the object of the verb is the same as the subject. These do not decline for number and gender.
 

Accusative	się (siebie for emphasis)
Genitive	siebie
Locative	sobie
Instrumental	sobą
Dative	sobie

Possessive pronouns:
These are used to express the possession of an object. These are actually adjectives, therefore declined as adjectives.
 

Demonstrative pronouns:
These pronouns are declined as demonstrative adjectives.
 

Interrogative pronouns:
The pronouns jaki/jaka/jakie, który/która/które and czyj/czyja/czyje are declined as adjectives therefore here I will only explain kto, co, nikt and nic.
In fact nikt is the negative form of kto, and nic the negation of co.
 

	kto	nikt	co	nic
Nominative	kto	nikt	co	nic
Accusative	kogo	nikogo	co	nic
Genitive	kogo	nikogo	czego	niczego
Locative	kim	nikim	czym	niczym
Instrumental	kim	nikim	czym	niczym
Dative	komu	nikomu	czemu	niczemu

The genitive of co (czego) together with the preposition dla forms the word dlaczego. But often this word is replaced by the dative of co (czemu).
 

Distributive pronouns:
These decline as an adjective.
Note: żaden requires a double negation.
 

Relative pronouns:
Który/która/które (see interrogative pronouns) is often replaced by co in speech, and always after to and kto. W and który is often shorted to gdzie.
 

Indefinite pronouns:
There are two ways to form them, 1st by adding ś and 2nd by adding kolwiek.
You add ś if you want to express "some". To express "at all" or the suffix "ever" you use kolwiek. Both endings are not declineable.