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Ostaa Conjugation

ostaa means "to buy" in Finnish. Present: minä ostan, sinä ostat, hän ostaa, me ostamme, te ostatte, he ostavat. Below: all 46 tenses we teach, with examples.

Present Preesens

Weak-grade stem + personal endings (-n, -t, vowel lengthening, -mme, -tte, -vat/-vät). It also covers the future, because Finnish has no separate future tense; context and time words (huomenna, ensi viikolla) show it.

Imperfect (Simple Past) Imperfekti

Past stem in -i- + endings. It is the normal narrative past and also answers 'did you ...?'. Gradation often returns the strong grade in the 3rd person (luin but luki).

Perfect Perfekti

Present of olla + past active participle (-nut/-nyt; plural -neet). Used for results and experience up to now, as in English, often with jo (already) or koskaan (ever).

Pluperfect Pluskvamperfekti

Imperfect of olla + past active participle. Used for something finished before another past moment.

Present (Negative) Preesens, kielteinen

The negative verb (en, et, ei, emme, ette, eivät) + the bare present stem (connegative, weak grade, no personal ending). The negative verb carries person; the main verb never changes.

Imperfect (Negative) Imperfekti, kielteinen

Negative verb + past active participle (singular -nut, plural -neet). The participle agrees in number with the subject, not the person.

Perfect (Negative) Perfekti, kielteinen

Negative verb + ole + past active participle.

Pluperfect (Negative) Pluskvamperfekti, kielteinen

Negative verb + ollut/olleet + past active participle.

Present Passiivin preesens

Stem + -taan/-tään (with strong grade after the stem vowel change). Finnish passive has no agent and no person: it means 'one / people do', and in everyday speech it replaces the 'we' form (me puhutaan).

Imperfect (Simple Past) Passiivin imperfekti

Passive stem + -ttiin/-tiin (-ttiin after strong stems).

Perfect Passiivin perfekti

on + past passive participle (-ttu/-tu).

Pluperfect Passiivin pluskvamperfekti

oli + past passive participle.

Present (Negative) Passiivin preesens, kielteinen

ei + passive stem without -an (no ending). Perfect negative: ei ole + participle; pluperfect negative: ei ollut + participle.

Imperfect (Negative) Passiivin imperfekti, kielteinen

ei + past passive participle.

Present Conditional Konditionaalin preesens

Stem + -isi- + personal endings. It is used for polite requests, wishes and hypotheticals ('would'), in both the main and the jos-clause.

Perfect Conditional Konditionaalin perfekti

olisi- forms + past active participle: 'would have'. Used for unreal past situations and regrets.

Present Conditional (Negative) Konditionaalin preesens, kielteinen

Negative verb + conditional 3rd-person form (it never changes for person).

Perfect Conditional (Negative) Konditionaalin perfekti, kielteinen

Negative verb + olisi + past active participle.

Passive Present Conditional Passiivin konditionaali

Passive stem + -ttaisiin/-taisiin. Impersonal 'would'.

Passive Perfect Conditional Passiivin konditionaalin perfekti

olisi + past passive participle. Negative: ei olisi + participle; present negative: ei + conditional without -n (ei puhuttaisi).

Present Potential Potentiaalin preesens

Stem + -ne- + personal endings. Literary and formal; expresses probability ('probably, presumably'). Rare in speech; the commonest forms are lienee, tullee and tietänee.

Perfect Potential Potentiaalin perfekti

lie- forms + past active participle: 'has probably ...'. Newspaper and legal style.

Present Potential (Negative) Potentiaalin preesens, kielteinen

Negative verb + potential stem without personal ending (connegative -ne).

Perfect Potential (Negative) Potentiaalin perfekti, kielteinen

Negative verb + liene + past active participle.

Passive Present Potential Passiivin potentiaali

Passive stem + -ttaneen. Very rare, bureaucratic. Negative: ei puhuttane.

Imperative (Affirmative) Imperatiivi, myönteinen

2nd singular is the bare stem. The 1st plural (let us), 2nd plural and the 3rd persons (let him / her / them) use the strong-grade stem + -kAAmme / -kAA / -kOOn / -kOOt. The polite request is usually the conditional rather than the imperative.

Imperative (Negative) Imperatiivi, kielteinen

Special negative verb: älä (you), älkäämme, älkää, älköön, älkööt + the verb in -ko/-kö. Singular: älä + bare stem.

Imperative Perfect Imperatiivin perfekti

olkoon / olkoot + past active participle. Rare, formal (contracts, mathematics, ceremonial language); only 3rd person is normal. Negative: älköön olko + participle.

Passive Imperative Passiivin imperatiivi

Passive stem + -kOOn: 'let it be done'. Negative: älköön + stem + -kO.

First Infinitive I infinitiivi

The dictionary form (-a/-ä, -da/-dä, -la/-na/-ra/-sta, -ta/-tä). It follows verbs such as haluta, voida, osata, aikoa and täytyy.

First Infinitive, Long Form I infinitiivin pitkä muoto

Infinitive + -kse- + possessive suffix (-ni, -si, -nsA / -An, -mme, -nne). Means 'in order to'; formal and written.

Second Infinitive, Inessive II infinitiivin inessiivi

Stem + -essa/-essä (+ possessive suffix if the subject differs from a noun). Means 'when / while doing'. The subject, if any, is in the genitive.

Second Infinitive, Instructive II infinitiivin instruktiivi

Stem + -en: manner ('by ...ing, while ...ing'), mostly in fixed phrases and written style.

Third Infinitive, Inessive III infinitiivin inessiivi

-ma/-mä stem + -ssa/-ssä: 'in the middle of doing'. The commonest of the III forms in everyday speech.

Third Infinitive, Elative III infinitiivin elatiivi

-ma stem + -sta/-stä: 'from / after doing' (also 'stop doing').

Third Infinitive, Illative III infinitiivin illatiivi

-ma stem + -an/-än: direction towards an action ('to do'). Used with mennä, tulla, ruveta, alkaa, auttaa, oppia.

Third Infinitive, Adessive III infinitiivin adessiivi

-ma stem + -lla/-llä: 'by doing'.

Third Infinitive, Abessive III infinitiivin abessiivi

-ma stem + -tta/-ttä: 'without doing'.

Fourth Infinitive IV infinitiivi

-minen: the verbal noun ('the act of ...ing'); it declines like a noun and works as 'to X' as a subject.

Fifth Infinitive V infinitiivi

-maisillaan + possessive suffix: 'on the point of doing'. Rare, literary.

Present Active Participle Aktiivin preesensin partisiippi

-va/-vä (from the 3rd plural). Used like an adjective or as a relative clause ('who/which does').

Past Active Participle Aktiivin perfektin partisiippi

-nut/-nyt (plural -neet). Forms the perfect and pluperfect; also an adjective ('who has done').

Present Passive Participle Passiivin preesensin partisiippi

-ttava/-ttävä: 'that can/must be done'. Expresses necessity or possibility.

Past Passive Participle Passiivin perfektin partisiippi

-ttu/-tty: 'was done'. Forms the passive perfect; also an adjective.

Agent Participle Agenttipartisiippi

-ma/-mä: 'done by (someone)'. The agent is in the genitive and precedes the participle; formal written style.

Negation Participle Kieltopartisiippi

-maton/-mätön: 'un-, not having ...ed, -less'.

Examples

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