Nouns: Plural Forms

01

The -t Plural

A plural subject, and a complete plural object, take -t added straight to the dictionary form.

• kissa → kissat

  cat → cats

• Lapset ovat koulussa.

  The children are at school.

• Kaupat ovat auki.

  The shops are open.

• Ostin kengät.

  I bought the shoes. (complete plural object)

02

The -i- Plural, Everywhere Else

As soon as the noun takes any other ending — in, from, on, to, or the open-amount ending — the -t disappears and an -i- appears instead, wedged between the stem and that ending.

• Asun vanhoissa taloissa.

  I live in old houses.

• talo-i-ssa — stem, then the plural -i-, then the "in" ending
• vanho-i-ssa — the adjective is built the same way and matches it piece for piece

• Annan lahjat lapsille.

  I give the gifts to the children.

• Pidän vanhoista kirjoista.

  I like old books.

03

The Stem Vowel Often Shifts Before -i-

Adding the -i- frequently changes the vowel right before it. The two most common shifts are a → o and the dropping of a final a/ä. The past tense uses an -i- too, and it triggers the same changes, so the pattern is worth recognising in both places.

• sana → sanoja

  word → words (a → o)

• kissa → kissoja

  cat → cats (a → o)

• kylä → kylissä

  village → in the villages (ä drops)

04

After a Number: Singular

There is one place where no plural appears at all. After a number above one the noun stays singular and takes -a/-ä, the ending for an amount left open. "Two cats" is kaksi kissaa, never a plural.

• kaksi kissaa

  two cats

• kolme taloa

  three houses