Laefèvæšii has 17 cases which are divided into three groups:
> 1st group – “basic cases” - includes 6 cases: nominative, genitive, dative, accusative, locative and instrumental;
> 2nd group – “additional cases” - includes 3 cases: vocative, partitive and equative;
> 3rd group – “sub-cases” - includes 8 cases: terminative, egressive, elative, illative, superessive, inessive, temporal and antenssive.
“Additional cases” and “sub-cases” can be replaced with”basic cases”:
> nominative can replace vocative and partitive
> genitive can replace equative, terminative, egressive and elative
> accusative can replace illative
> locative can replace superessive, inessive and temporal
> instrumental can replace antessive
Example: Ástwaliämi vásnala. - Ástwaliämi là vásnada. (I went into house.)
Explanation: in the first sentence is used illative case (vásnala – into house), in the second sentence is used accusative (vásnada – house) but here it's also used preposition là which means into.
Cases temporal and antessive are used only for time expressions.
Partitive case is not used in singular and dual, it's only used in plural. For numbers from 3 to 19 partitive has special endings, for larger numbers (20 and more) is used “general ending”.
Locative and instrumental case are prepositional cases.