"We do not have a shirt."
Translation:Nie mamy koszuli.
These last two, "k" and "g" are called "velars" in some texts about Polish grammar.
But the same texts very rarely explain the meaning of velar, much less give a list as to what the velar consonants are for Polish, so its worth mentioning here that these are the velar consonants for Polish.
Velar is a term used by linguists it seems and they apply it to consonants in all/any language. Other languages may have a bigger or smaller list of velar consonants.
Technically, ch and h are velars as well, but they can be followed by y, unlike k and g.
Polish has also velar n, which appears only before k and g – in English, this sound is written as ng. You can also count ł (IPA: /w/) as velar: https://en.wikipedia.org/wiki/Velar_consonant
Meanwhile in Russian, all velars, к, г and х, have to be followed by и instead of ы, and н is never velar, even before к or г. Yet more tiny differences.
In my Polish PONS grammar table it says clearly that the feminine form of the genitive is formed with -y unless the root ends on -g or -k as in książka which then becomes książki. There is no mention of a discrimination between hard and soft consonants here. However I read the wikipedia article on koszula and the word search for koszuly was negative. So I am very confused.
I find the book referenced below very useful. I have it on kindle. Of course I had to buy it but it wasn't much.£6.71
It gives a whole table of endings for all the possible possible combinations of nouns (also adjectives, verb conjugations etc.)
E.g. for noun declensions, it gives the table including the following entry:
fem. sing. gen. = -y | -i
(left | right)
..and then says...
"Feminine Nouns 1. Hard stems. Hard-stem feminine nouns in -a, like kobieta woman, take endings on the left; soft-stem feminine nouns in —, like twarz face, take endings on the right; soft-stem feminine nouns in -a (like ulica street) or in -i (like gospodyni landlady) take the highlighted alternatives. For charts of full declensions, see below. 2. Soft stems. Soft-stem diminutive and affectionate names have a vocative singular in -u: Basia Barb → voc.sg. Basiu."
Then you have examples of the velars too in the list of example ("k", "g")
Swan, Oscar (2008-10-12). Polish Verbs & Essentials of Grammar, Second Edition (Verbs and Essentials of Grammar Series) (Kindle Locations 422-428). McGraw-Hill Education. Kindle Edition.
Yes, this is genitive. Do not get misguided by the name of the case, the use of Genitive in Polish language is much broader than the name of the case might suggest. Genitive is used:
In negations - "ojciec(nom.) nie ma koszuli(gen.)" [father has no shirt], "nie ma chleba(gen.)" [there is no bread]. There are situations to express negation without Genitive ("żaden ptak(nom.) nie śpiewa" [no bird is singing], "to nie pies(nom.)" [this is not a dog], "to nie jest ani pies(nom.) ani kot(nom.)" [it is neither a dog nor a cat]) - but you should probably remember that the basic form of negation is with Genitive.
To describe ownership when used with a noun - "koszula(nom.) ojca (gen.)" [the shirt of the father]. But when the ownership is expressed with a pronoun, the case of pronoun has to be the same as case of possessed noun "moja(nom.) koszula(nom.)" [my shirt], "nie ma mojej(gen.) koszuli(gen.)" [there is not my shirt].
To describe a part of something - "kawałek(nom.) chleba (gen.)" [a piece of bread]; "odcinek(nom.) serialu (gen.)" [an episode of tv-series]. Because the genitive means a part of something whole, the use of case can change the meaning of phrase: "wsyp sól(acc.) do zupy" [Pour the salt (all the salt that you have) into the soup] - "wsyp soli(gen.) do zupy" [Pour some salt into the soup]; "zjedli (cały) chleb(acc.)" [they ate (the whole) brad (a whole loaf or all the available bread)] - "zjedli (trochę) chleba(gen.)" [they ate (some) bread] (the use of cały/trochę is optional - without it the phrase means the same, but with them it is clearer)
In comparisons - "bułka(nom.) lepsza od chleba(gen.)" [A roll better than bread]
To express separation from sth/sb - "oddzielić dziecko(acc.) od matki(gen.)" [to separate a child from the mother], "wyjąć zapałkę(acc.) z pudełka(gen.)" [to take a match out of the box].
Many prepositions require that the following noun is in Genitive case: "od" [from], "z" [from, off, out of] (attention: "z" also means [with] - but in that meaning the Instrumental case is required), "do" [to], "dla" [for], "u" [at], "bez" [without], "prócz" [except], "oprócz" [except], "obok" [by], "koło" [by], "około" [about, at about], "naokoło" [around], "blisko" [near, close to], "wśród" [between, in between], "znad" [from above], "spod" [from under], "naprzeciw" [in front of], "naprzeciwko" [in front of, opposite], "podczas" [during], "według" [acccording to], "zamiast" [instead of]. Samples: "od domu(gen.) do domu(gen.)" [from house to house], "dla mojej(gen.) babci(gen.)" [for my grandma], "spotkamy się około siódmej(gen.)" [we meet at about seven o'clock], "jesteś naprzeciwko Sądu(gen.)" [you are in the front of the Court].
In Polish language, the verb rules the case of the noun used with it (sometimes there are more cases possible, each giving a different meaning to the phrase). There are verbs that require just Genitive - "używać narzędzia(gen.)" [to use a tool]; "udzielać wywiadu(gen.)" [to give an interview], "zabić drozda(gen.)" [to kill a mockingbird], "dolać oliwy(gen.) do ognia(gen., see above)" [to add fuel (oil) to the flames].
It is used to describe activities by the noun derived from verb, even if the original verb requires a noun in accusative: "czytanie(n.) książki(gen.)" [reading of a book] - "czytać(v.) książkę(acc.)" [to read a book]
ATTENTION: the form of Genitive singular case is often the same as Accusative plural or Nominative plural (see this thread ), or Genitive plural. You may like to see the tables here or here. Therefore, it is important to understand when Genitive singular/plural should be expected.
Genitive has taken the function of the Ablative case which existed in ancient Polish, but does not exist any more, and this may explain why it is a particularly difficult case. You may be also interested in this thread .
Disclaimer: I am not a linguist, so perhaps I have omitted some important use of Genitive. If I recall something, I will edit this post.
Because "koszulę" is Accusative case. Accusative is used in Polish for example to confirm possession with the verb "mieć" [to have] - in fact, many verbs require usage of Accusative in affirmative phrases (f.ex. "czytać" [to read] , "reklamować" [to advertise], "jeść" [to eat], "wybierać" [to choose], "lubić" [to like])
But when the form of phrase is negative - the case automatically changes to Genitive, which would be "koszuli". See also above.