The Conditional -isi-: 'would' | Finnish Grammar

The conditional (Finnish konditionaali) is the mood of things that are not asserted as fact — actions imagined, wished for, or dependent on some condition. It is Finnish's single equivalent of English "would": puhuisin "I would speak," tulisi "would come," olisi "would be." Where English needs an extra word (would), Finnish does the whole job with one syllable slipped inside the verb: -isi-. This page introduces the mood and what it is for; the type-by-type mechanics get their own page.

There is no word for "would"

The first thing an English speaker has to unlearn is the hunt for a separate modal. Finnish has no auxiliary word for "would." The meaning lives entirely in a marker, -isi-, inserted between the verb stem and the personal ending:

Person	puhua → conditional	English
minä	puhu·isi·n	I would speak
sinä	puhu·isi·t	you would speak
hän	puhu·isi	he/she would speak
me	puhu·isi·mme	we would speak
te	puhu·isi·tte	you (pl.) would speak
he	puhu·isi·vat	they would speak

The dots above just show the seams — you would never write them. The pattern is: stem + isi + the ordinary ending. And it is the same -isi- for every verb in the language:

Verb	Conditional (I / he)	English
tulla (come)	tulisin / tulisi	would come
saada (get)	saisin / saisi	would get
tehdä (do)	tekisin / tekisi	would do
olla (be)	olisin / olisi	would be

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Notice that the third person singular is just puhuisi — bare -isi with no ending, exactly as the past tense third person is bare -i (puhui). The conditional and the past share this "no ending in the third person singular" behaviour.

Present fact vs. conditional hypothesis

The cleanest way to feel the mood is a minimal pair. The present states a fact; the conditional lifts the same action into the hypothetical.

Puhun suomea joka päivä töissä.

I speak Finnish every day at work.

Puhuisin suomea paremmin, jos harjoittelisin enemmän.

I would speak Finnish better if I practised more.

The first sentence reports reality; the second reports a possibility that depends on a condition. That is the essence of the mood — the action lives in the realm of what if, not what is.

Ostaisin ison talon meren rannalta, jos voittaisin lotossa.

I would buy a big house by the sea if I won the lottery.

What the conditional does

As a chapter opener, here is the map of the territory. Each of these gets fuller treatment on its own page, but you should recognise all four uses on sight.

1. Hypotheticals and unreal situations. The core meaning: an action imagined under some condition, real or unreal.

Ilman sinua en pärjäisi.

Without you I wouldn't cope.

2. Wishes and preferences. Haluaisin "I would like" is one of the most useful phrases a beginner learns — softer and more natural than the blunt present haluan "I want."

Haluaisin kupin kahvia ja palan sitä omenapiirakkaa.

I'd like a cup of coffee and a piece of that apple pie.

3. Politeness — softening requests and questions. Turning a demand into the conditional is the standard Finnish way to be courteous, much like English "could you" / "would you." (See conditional politeness.)

Voisitko auttaa minua hetken?

Could you help me for a moment?

Olisi mukavaa nähdä sinut taas joskus.

It would be nice to see you again sometime.

4. The "then" half of if-sentences. In a full conditional sentence, both halves usually take -isi-: jos + conditional, conditional — the details live on the if-sentences page.

Jos minulla olisi enemmän aikaa, matkustaisin ympäri maailmaa.

If I had more time, I would travel around the world.

The false friend: English "would" for past habits

Here is the trap that catches almost every English speaker. English uses would for two completely different things, and Finnish only shares one of them. When English would means past habit — "every summer we would go to the cottage" — it is not conditional at all; it is just repeated past action. Finnish expresses that with the plain past tense (imperfekti), never the conditional.

Kävimme mökillä joka kesä, kun olin lapsi.

We would go to the cottage every summer when I was a child.

Using kävisimme here would be wrong — it would mean "we would go (hypothetically, under some condition)," not "we used to go." Ask yourself: does the English would mean what if (→ conditional) or used to (→ plain past)? Only the first becomes -isi-.

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Two Englishes hide inside one word. Would = "hypothetically" → Finnish -isi- (kävisimme). Would = "used to, habitually" → Finnish plain imperfekti (kävimme). Translate the meaning, not the word.

A preview of the stem changes

One reason the conditional feels familiar once you build a few is that its -isi- begins with the very same -i- that forms the past tense. That shared -i- triggers many of the same stem adjustments — a final -e drops, a long vowel contracts — so the conditional stem often looks like the imperfekti stem. The systematic version of this, verb type by verb type, is the whole subject of the formation page.

Common Mistakes

❌ Minä would puhua suomea, jos voisin.

Incorrect — there is no separate word for 'would'; it is the marker -isi- inside the verb.

✅ Puhuisin suomea, jos voisin.

I would speak Finnish if I could.

❌ Lapsena kävisimme mökillä joka kesä.

Incorrect — a past habit is the plain imperfekti, not the conditional: kävimme.

✅ Lapsena kävimme mökillä joka kesä.

As a child we would go to the cottage every summer.

❌ Hän puhuisii englantia, jos osaisi.

Incorrect — the third person singular is bare -isi, with no doubled vowel: puhuisi.

✅ Hän puhuisi englantia, jos osaisi.

He would speak English if he knew how.

Key Takeaways

The conditional is Finnish's "would": the mood of hypotheticals, wishes, and polite requests.
It is built with the marker -isi- between stem and ending — there is no separate modal word.
Third person singular is bare -isi (puhuisi, tulisi, olisi), like the past tense's bare -i.
English would meaning "used to" is not conditional — Finnish uses the plain past tense instead.
For how -isi- attaches across the verb types, see forming the conditional.

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