Comitative case

The comitative case (abbreviated com), also known as the associative case (abbreviated ass), is a grammatical case that denotes companionship, and is used where English would use "in company with" or "together with"^{[citation needed]}. Among other languages, it is found in Korean, Finnish, Hungarian, Mongolian, Estonian, Japanese and many Australian Aboriginal languages where it is very commonly used to form names of places and languages^{[citation needed]}.

Estonian

In the Estonian language singular comitative is formed by adding the suffix '-ga' to the genitive in case of singular^{[citation needed]}:

• nina (nominative: nose) → nina (genitive: of nose) → ninaga (comitative: with a nose)
• koer (nominative: dog) → koera (genitive: of dog) → koeraga (comitative: with a dog)

And by adding the suffixes '-de' and '-ga' to the singular partitive in case of plural, thus making first a plural genitive case and then adding the comitative suffix:

• leht (nominative: leaf, page) → lehte (partitive: leaf) → lehtede (genitive: of leaves) → lehtedega (comitative: with leaves)
• kass (nominative: cat) → kassi (partitive: cat) → kasside (genitive: of cats) → kassidega (comitative: with cats)

In the Estonian language comitative is also used to denote when something is used as an implement - kirvega (with axe / using an axe) or as a means of transport laevaga (by boat)^{[citation needed]}.

Finnish

In the Finnish language, the comitative is rare and seldom used in spoken Finnish. The suffix -ne is used alone only when it is an attribute of another word, otherwise additional possessive suffix must be added, such as -ne+en, e.g. suurine vuorineen "with its large mountains". The Finnish literary comitative expresses only possessions or attributes, and as such does not replace the preposition "from". It has only a plural, which is, paradoxically, used to denote both the singular and the plural, e.g. tyttö koirineen "girl with her dog(s)".

In the expressions corresponding to the Estonian ones above, the adessive may be used, e.g. lehdillä "with leaves" or laivalla "by boat". The idea of "being in company" is expressed with genitive + kanssa, e.g. tyttö koiran kanssa "girl with dog". In spoken Finnish, this abbreviates to a clitic very similar to the Estonian comitative, -nkaa (via -nkans). It is debatable if this is a grammatical case, because it does not obey vowel harmony; that is, there is no form -nkää. Some dialects do have such a form, however.

Japanese

In the Japanese language, the comitative uses the same particle as the coordinating conjunction to (and)^{[citation needed]}.

Yūbe tomodachi-to eiga-o mi-ni itta. ((I) went to the movies with friends last night.) (Lit: last.night friend(s)-with movie(s)-acc see-to went) Compare: tomodachi-to kazoku-wa hitsuyō da. (Friends and family are important.) (Lit: friends and family-TOP necessity COPULA.)

English

English also exhibits grammatical behavior which may be described as instances of the comitative case. The most prominent example is with the first person singular pronoun, although higher registers tend to avoid this usage via editing:

• My dad and me haven't ever really been close.
• Me and my wife's favorite fish is mackerel.