How do Latin nouns work?

Answer 1

Latin nouns, adjectives, pronouns, and participles are all declined - which means they have a different suffix depending upon which way they are used in a sentence. This is why Romans could mix up the order totally and still understand "Blond shaggy dog girl bit" more easily in Latin that we do in English. Nouns have three qualities: gender, number (single vs plural), case. There are 5 basic cases (and 2 special ones) :

Nominative for subjects and predicate nominative

Genitive to show ownership

Dative for indirect objects

Accusative for direct objects and as objects of most prepositions

Ablative for objects of prepositions: from, with/without, by, in/on

One changes the suffix for the usage above. There are 5 possible patterns for nouns, 99% belong to 1st, 2nd, or 3rd. Few belong to 4th and 5th. Adjectives belong to the same 1st, 2nd, or 3rd. Any word can belong only to one of the declension patterns, it cannot jump into another declension pattern.

Answer 2

Nouns in Latin are categorized by gender (masculine, feminine, neuter), number (singular, plural), and by case. A noun's case identifies its role in the sentence. For example, if the noun is in the Nominative case, we know that the noun has to be the Subject of the sentence. If the noun is a word like "femina" (woman), we can infer that this word is Nominative, singular, and feminine, meaning the woman is the subject, and there is only one.