Declension in Polish – 7 cases of Polish language
In polish both nouns and adjectives change their form (especially the endings) depending on their function in a sentence and overall context. Let’s look at the example below:

1. To jest (co?) mały kot.
This is a small cat.
2. Tu nie ma (czego?) małego kota.
There is no small cat.
3. Przyglądam się (czemu?) małemu kotu.
I am looking at a small cat.
4. Chcę adoptować (co?) małego kota.
I want to adopt a small cat.
5. Idę na spacer z (czym?) małym kotem.
I’m going for a walk with a small cat.
6. Myślę o małym kocie.
I am thinking about a small cat.
7. O, mój kochany mały kocie!
Oh, my lovely small cat!

As you can see, both the adjective and the noun change their endings, the main part of the word still remains the same.

There are 7 cases in Polish: 1. Nominative (or in Polish – Mianownik), 2. Genitive (Dopełniacz), 3. Dative (Celownik), 4. Accusative (Biernik), 5. Instrumental (Narzędnik), 6. Locative (Miejscownik), 7. Vocative (Wołacz).
We will characterise each one in the next chapters.

It is usually pretty easy to spot a part of the word that remains the same – this is the stem or a topic of the word. Unfortunately, in some cases stems can also change a little bit. Look at the example:

Nominative (Mianownik) mały kot
Genitive (Dopełniacz) małego kota
Dative (Celownik) małemu kotu
Acusative (Biernik) małego kota
Instrumental (Narzędnik) małym kotem
Locative (Miejscownik) małym kocie
Vocative (Wołacz) mały kocie

As you can see, in case of the adjective ‘mały’ (small) the is mał- and it has different endings depending on the grammatical case (-y,-ego, -emu, -ym).

The noun ‘kot’ (a cat) also has a stem: kot-, which has different endings (-a, -u, -em, -e, -e). But look what happens in the last two cases – Locative and Vocative. The topic kot- changes to koci- with the ending -e. This means the letter ‘t’ changes to letters ‘ci’ (which make the polish ‘ć’ sound). This is called softening of the stem and we will touch on that topic later.

If you still are not sure as to why Polish people need to use do many grammatical cases, just look at another representation of how would it look like in English:

Nominative – To jest (kto?) kobieta
This is (who?) a woman.
Genitive – Naszyjnik (czyj?) kobiety.
Woman’s necklace. (whose necklace?)
Dative – Daję naszyjnik (komu?) kobiecie.
I am giving a necklace to a woman.
Accusative – Słyszę (kogo?) kobietę.
I hear (who?) a woman.
Instrumental – Biegam (z kim?) z kobietą.
I am running (with who?) with a woman.
Locative – Naszyjnik jest na (kim?) kobiecie.
The necklace is (where? on who?) on a woman.
Vocative – Kobieto! Wołam cię, proszę przyjdź do mnie!
Woman! I’m calling you, please come to me!

In fact, English also used to have cases and it still has some remaints, pay attention to what happens in this sentences:
This is my cat. The cat belongs to me. The cat is mine.

In the next lesson we will explain the usage of Nominative case with nouns.