One point of view that might help is considering cases as being an alternative to prepositions. English has three cases - nominative, indicating the subject of

One point of view that might help is considering cases as being an alternative to prepositions. English has three cases - nominative, indicating the subject of a sentence; accusative, indicating the direct object; and genitive, indicating possession. Rather than using the genitive, we can also use a preposition: David's book, or the book of David. German has a fourth case for the indirect object. Where English has to use a preposition (e.g. I gave the book to him), German uses the dative case (Ich gab ihm das Buch). Finnish takes the concept much further - it has fifteen cases, which can be used where English would use a preposition. For example, the abessive case is used where English would use "without", the comitative for "together" or "with". So cases are not types, they are relations, indicating the role of the noun in the sentence.