Source: Oulton. N.R.R. 2010. So You Really Want To Learn Latin Book I Tenterden, Great Britain: Galore Park Publishing (1999).
Chapter IV & V – Nouns of the 2nd declension
Nouns like: “annus, annī, m. = Year”
Nominative – annus – [Year (subject)]
Vocative – anne – [O year! (addressing)]
Accusative – annum – [Year (object)]
Genitive – annī – [Of a year]
Dative – annō – [To or for a year]
Ablative – annō – [By, with or from a year]
Nominative – annī – [Years (subject)]
Vocative – annī – [O years! (addressing)]
Accusative – annōs – [Years (object)]
Genitive – annōrum – [Of the years]
Dative – annīs – [To or for the years]
Ablative – annīs – [By, with or from the years]
The other main type of 2nd declension noun goes like bellum = war. Nouns that end in -um go like bellum and are neuter, i.e. neither masculine nor feminine. The main difficulty with neuter nouns is that there is no difference between their nominative, vocative and accusative cases, so working out whether a noun is the subject or the object is that much more difficult.
Nouns like: “bellum, bellī, n. = War”
Nominative – bellum – [War (subject)]
Vocative – bellum – [O war! (addressing)]
Accusative – bellum – [War (object)]
Genitive – bellī – [Of a war]
Dative – bellō – [To or for a war]
Ablative – bellō – [By, with or from a war]
Nominative – bella – [Wars (subject)]
Vocative – bella – [O wars! (addressing)]
Accusative – bella – [Wars (object)]
Genitive – bellōrum – [Of the wars]
Dative – bellīs – [To or for the wars]
Ablative – bellīs – [By, with or from the wars]
So how do we cope then? We see the ending -um but can no longer be sure that this is an accusative singular ending (as it would be for annus type nouns). Again, we fall back on common sense and, of course, obeying the rules of translation carefully.
There are two more types of the 2nd declension nouns, both very similar.
Nouns like: “puer, puerī, m. = Boy”
Nominative – puer – [Boy (subject)]
Vocative – puer – [O boy! (addressing)]
Accusative – puerum – [Boy (object)]
Genitive – puerī – [Of a boy]
Dative – puerō – [To or for a boy]
Ablative – puerō – [By, with or from a boy]
Nominative – puerī – [Boys (subject)]
Vocative – puerī – [O boys! (addressing)]
Accusative – puerōs – [Boys (object)]
Genitive – puerōrum – [Of the boys]
Dative – puerīs – [To or for the boys]
Ablative – puerīs – [By, with or from the boys]
Nouns like: “magister, magisterī, m. = Master”
Nominative – magister – [Master (subject)]
Vocative – magister – [O master! (addressing)]
Accusative – magistrum – [Master (object)]
Genitive – magistrī – [Of a master]
Dative – magistrō – [To or for a master]
Ablative – magistrō – [By, with or from a master]
Nominative – magistrī – [Masters (subject)]
Vocative – magistrī – [O master! (addressing)]
Accusative – magistrōs – [Masters (object)]
Genitive – magistrōrum – [Of the masters]
Dative – magistrīs – [To or for the masters]
Ablative – magistrīs – [By, with or from the masters]
These nouns use identical endings to annus except in the nominative and vocative singular. The difference between the two is that nouns like puer ‘keep their e’ whereas nouns like magister ‘drop their e’.
The Six Cases (Repetition)
- The Nominative case is used to show that the noun is the subject of the sentence, i.e. that the noun is the person doing the verb. E.g. ‘The girl loves the farmer’ = puella agricolam amat.
- The Vocative case is used for addressing the noun. E.g. ‘O sailors, you love the island’ = nautae, īnsulam amātis.
- The Accusative case is used to show that the noun is the object, i.e., the person or thing to which the verb is being done. E.g. ‘He loves the girl‘ = puellam amat.
- The Genitive case is used for ‘of’. The genitive case is the possessive case. In English we either use the word ‘of’ or else we use an apostrophe. In Latin, the ‘possessor’ (i.e. the noun that is doing the possessing) is put into the genitive case and may come before or after the other noun. E.g. ‘The table of the farmer‘ / ‘The farmer’s table’ = mēnsa agricolae.
- The Dative case is used for the indirect object and is generally translated with ‘to’ or ‘for’. E.g. ‘The farmer sings to the girl‘ = agricola puellae cantat.
- The Ablative case is used for the instrument by means of which we do something. It is often translated by the words from, by or with, but (in the case of the latter two) only when these mean by means of. E.g. ‘They overcome the inhabitants by means of wisdom‘ = incolās sapientiā superant.
N.B. Latin has no definite or indefinite article. Thus mēnsa = table or the table or a table – the choice is yours.