In English the only case ending in nouns is that of the genitive (as in boy’s, men’s, etc.). Elsewhere the function of a noun is shown by its position in a clause (the difference in meaning between the policeman hit the demonstrator and the demonstrator hit the policeman depends solely on word order) or by a preposition: the demonstrator was hit by a car (here the part played by the car is indicated by the preposition by).

The basic functions of each of the six Latin cases are:

(a) The subject of a clause must be put in the nominative.

(b) When we address a person the vocative is used; this is often preceded by Ō and always followed by a mark of punctuation.

(c) The direct object of a verb must be put in the accusative; this case is also used after certain prepositions.

(d) The genitive expresses possession: Caesar’s chariot (in English we can also say the chariot of Caesar).

(e) The dative expresses the indirect object after verbs of giving and saying. In Calpurnia gave a new toga to Caesar the direct object is toga (answering the question gave what?), and the indirect object is Caesar (gave to whom?). Note that in English we can also say, with the same meaning, Calpurnia gave Caesar a new toga. In either case the Latin would be the same, with toga in the accusative and Caesar in the dative. As we will see, the dative has other uses as well. They can nearly always be translated by to or for.

(f) The uses of the ablative vary according to the noun involved and its context. With living beings such as puella it is used in conjunction with certain prepositions (ā puellā by a (the) girl, cum puellīs with (the) girls) and in two constructions we shall meet subsequently