Genitive case - dopełniacz

The genitive case is the case most often used case, outside the pages of the dictionary.  Here's when it is used:

For the direct object of negative sentences.

Nie lubię kawy (I don't like coffee)  kawy is the direct object of the sentence.

Expressing dates that things are on, like: 

on the 11th of November

jedenastego listopada

Expressing start and end times:

from 9am to 6pm

od dziewiątej do osiemnastej  - from 9th [hour] to 18th [hour]

The numbers are ordinal numbers (ninth rather than nine) and I think that because hour (godzina) is feminine, they take the genitive female form (they all seem to end in -ej)

To show possession in English, we add 's to the end of the name of the owner.  In Polish the name of the owner takes the genitive case.

Kawa Piotra - Piotr's coffee.

(Note that kawa is still in the nominative case.)

In stating the number of items when there are five or more of them.

pięć piw - five beers

NB piwo is a neuter noun

Nouns take the genitive case when they follow these prepositions:

od - from

z - from / out / of

do - to / towards / into

u - at someone's place (like chez in French)

bez - without

dla - for

blisko / koło - near (use either interchangeably)

obok - beside / next to

naprzeciwko - opposite

w czasie / podczas - during (interchangeable)

z powodu - because of / due to / owing to*

*in English stick to because of.  Some grammarians get their knickers in a twist over the use of due to.

After verbs like:

Uczyć się - to learn / study.  Uczę się polskiego.  I'm learning Polish.

Potrzebować - to need.

Szukać - to look for.

Używać - to use.

To talk about quantity and packaging.  Examples:

pół pizzy - half a pizza

butelka wody

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