The fourth infinitive

1. Use

When using certain verbs in connection with other verbs, you sometimes have to turn them into a substantive. In English, you do this by adding -ing to the verb (e.g. I enjoy reading). In Finnish, you can recognise this specific form by the ending -minen. The -minen form of the verb is the nounalized verb!

Note: advanced Finnish linguistic sources will make a distinction between -minen as a noun (teonnimi) and -minen as an infinitive. According to those sources, the fourth infinitive is limited to the nessessive use of the form. These sources consider the nounalized verb as a separate entity despite it having the exact same basic form. I don't see a need to consider these two separate entities. If you're an advanced learner, you can read more about this here, here and here

2. Formation

The fourth infinitive has the stem ending -minen. You add this ending to the strong stem of the verb, which you can find by taking the third person plural form, and removing the -vat.

Verb Third person plural Fourth infinitive
nukkua he nukkuvat nukkuminen
syödä he syövät syöminen
ajatella he ajattelevat ajatteleminen
tavata he tapaavat tapaaminen
häiritä he häiritsevät häiritseminen
rohjeta he rohkenevat rohkeneminen

This -minen form is just the basis of this fourth infinitive. Since you change verbs into substantives with it, the verbs get afflected into all the different cases! To do that, you treat the verb as a noun with ending -nen (like for example punainen or suomalainen). For example:

Case Nainen Hevonen Lukeminen Saaminen
Partitive naista hevosta lukemista saamista
Genitive naisen hevosen lukemisen saamisen
Inessive naisessa hevosessa lukemisessa saamisessa
Elative naisesta hevosesta lukemisesta saamisesta

3. Fixed endings

Some verbs require that the nounalized verb behind it is written in a specific case.


Verb Example Translation
aloittaa Aloitan laihduttamisen huomenna. I start dieting tomorrow
lopettaa Lopetin tupakoimisen 3 vuotta sitten. I quit smoking thee years ago.


Verb Example Translation
rakastaa Katri rakastaa laulamista. Katri loves singing.
harrastaa Venla harrastaa ratsastamista. Venla enjoys horseriding.
inhota Inhoan juoruilemista. I hate gossiping.
vihata Vihaatko lentämistä? Do you hate flying?
pelätä He pelkäävät hampaiden poraamista. They fear teeth-drilling.
suunnitella Suunnittelemme talon rakentamista. We plan the building of a house.


Verb Example Translation
pitää Pidättekö puutarhan hoitamisesta? Do you like taking care of the garden?
tykätä En tykkää tiskaamisesta. I don't like doing the dishes.
nauttia Nautin saunomisesta. I enjoy taking a sauna.

4. Rotation

When there is an object in the sentence, it almost always gets put in the genitive case, and is situated in front of the 4th infinitive:

Tykkään siitä, että voin laittaa ruokaa.
-> Tykkään ruoan laittamisesta.

Minä istutin kukkia. Nyt minä olen valmis.
-> Lopetin kukkien istuttamisen.

Nautin, jos otan aurinkoa.
-> Nautin auringon ottamisesta

Suunnittelen, että haluan etsiä työtä
-> Suunnittelen työn etsimistä