-ma/-mä

The agent participle (agenttipartisiippi) is a powerful tool for creating concise sentences. Unlike the passive past participle, which hides the doer, the agent participle must name the doer. It is primarily used with transitive verbs (verbs that can take an object), though it can occasionally appear with certain intransitive verbs. Note that many simplified learner resources teach that it is 'transitive only' as a rule of thumb, even though intransitive usage for locations or paths is grammatically correct.

1. Formation:
Take the strong vocalic stem (the same stem used for the third infinitive) and add -ma or -mä based on vowel harmony. The -ma/-mä suffix does not trigger consonant gradation, so you always use the strong stem.

• lukea (to read) → luke- + -ma = lukema
• leipoa (to bake) → leipo- + -ma = leipoma (not leivoma)
• rakentaa (to build) → rakenta- + -ma = rakentama (not rakennama)
• syödä (to eat) → syö- + -mä = syömä

2. The Agent and Word Order:
The agent doing the action is always in the genitive case. When used as a noun modifier, the phrase (Agent + Participle) comes before that noun. It can also be a predicate: Kakku on äidin tekemä. While the participle declines to match the head noun, the genitive agent stays exactly the same. If the agent is a pronoun, you must add a possessive suffix to the participle in standard written Finnish. The possessive suffix attaches after the case ending (e.g., ostama-ssa-ni). Note that 1st and 2nd person genitive pronouns (minun, sinun, meidän, teidän) can be omitted because the suffix already identifies the person. For 3rd person pronouns (hänen, heidän), the pronoun is mandatory unless the agent is the same as the subject of the sentence, in which case the pronoun must be omitted and only the possessive suffix is used (e.g., Hän luki kirjoittamansa kirjan).

• äidin tekemä ruoka (food made by mom)
• (minun) tekemäni ruoka (food made by me)

3. Syntactic Relationship:
The noun being described by the agent participle is usually the receiver (object) of the action, never the doer (subject). It typically replaces an object relative clause. For example, miehen ostama auto means 'the car bought by the man'. You cannot say auton ostama mies to mean 'the man who bought the car'—that would mean 'the man bought by the car'! With intransitive verbs, the modified noun often describes a location, instrument, or path (e.g., pojan nukkuma sänky - the bed slept in by the boy).

4. Agreement:
Because the participle acts as an adjective, it must match the case and number of the noun it describes. The genitive agent remains unchanged.

• Luin äidin kirjoittamaa kirjaa. (I was reading the book written by mom - Partitive agreement).

5. Negative Form:
While the negative participle itself (-maton/-mätön) is highly productive and common (e.g., lukematon kirja - an unread book), using it with a specific agent attached (e.g., äidin tekemätön ruoka) is rare and can sound clunky. For simple negative statements with an agent, Finns typically prefer a standard relative clause (e.g., ruoka, jota äiti ei tehnyt - food that mom didn't make).

6. Usage Nuance:
The agent participle does not have separate present and past forms. While often translated as past tense ('written by'), it can also describe ongoing or habitual actions, such as kaikkien tuntema mies (a man known by everyone) or äidin rakastama lapsi (the child loved by mom).

Endings Before a Possessive Suffix
Nominative plural -t and genitive singular -n disappear: ostamat + -ni → ostamani kirjat, ostaman + -ni → ostamani kirjan. Other cases retain their ending before the suffix: ostamassa + -ni → ostamassani talossa. In common colloquial speech, a genitive pronoun often replaces the possessive suffix for any person: mun ostamat kirjat, sen ostamat kirjat. The participle then retains ordinary case and number endings, as -t in ostamat. Standard written Finnish uses (minun) ostamani kirjat and hänen ostamansa kirjat.