tärkeisiin

Tärkeisiin is the plural illative form of the Finnish adjective tärkeä, meaning "important." In Finnish grammar, adjectives agree with the noun they modify in both number and case, so when the noun is plural and in the illative case, the adjective takes the corresponding illative plural form. Therefore tärkeisiin conveys "to important [things/areas/points]" or, more broadly, "the important ones" in a destination or focus sense.

Usage of tärkeisiin occurs with plural nouns that are in the illative case. The form is commonly seen in expressions about directing attention or action toward something considered important. For example, in the sentence Meidän on keskityttävä tärkeisiin asioihin, tärkeisiin modifies asioihin to mean "important matters" in the illative plural: we must focus on important matters.

Morphologically, tärkeisiin is built from the stem of tärkeä plus the illative plural suffix -isiin. The corresponding singular illative form is tärkeään, used with a singular noun in illative, such as tärkeään asiaan (“to an important matter”). Other related forms of the adjective tärkeä include the nominative plural tärkeät and the partitive plural tärkeitä, reflecting Finnish’s rich case and number system.

In summary, tärkeisiin is a grammatical form used to describe multiple important items or aspects in a context involving movement toward or focus on those items, typical in discussions of priorities, goals, or matters.