kouluista

Kouluista is the plural elative form of the Finnish noun koulu, meaning from the schools. In Finnish grammar, the elative case signals origin or source, and it can also be used to indicate the topic in certain constructions. The singular elative form is koulusta, while the plural elative form is kouluista. The form demonstrates how Finnish builds the plural elative by attaching the suffix -ista/-istä to the plural stem and adjusting phonology to fit the word.

Usage of kouluista commonly includes indicating origin from multiple schools, for example in phrases such as tutkimuksen tiedot kerättiin kouluista (the data for the study were collected from the schools). It can also appear in constructions where the topic or subject is expressed with the elative, for instance kirjoitus käsittelee kouluista käytettyjä opetussuunnitelmia (the article discusses curricula used in schools). The plural elative thus serves both source-related and topic-related functions depending on context.

Kouluista contrasts with related forms such as koulusta (singular elative, from the school), koulut (nominative plural, schools), kouluissa (inessive plural, in the schools), and kouluihin (illative plural, to the schools). Understanding kouluista thus involves recognizing the broader Finnish case system and how the suffix -ista/-istä interacts with number and vowel harmony.

See also: Finnish grammar, elative case, plural forms.