Learn Hardcore Finnish: Peitto on lämmin, joten nukun hyvin.

Because joten (“so/therefore”) joins two independent clauses. In standard Finnish, you put a comma before coordinating conjunctions like joten, mutta, vaan, sillä.

What’s the difference between joten and koska here?

joten = “so/therefore” and introduces the result. Cause → result: Peitto on lämmin, joten nukun hyvin.
koska = “because” and introduces the reason. Result → reason: Nukun hyvin, koska peitto on lämmin. You can also say: Peitto on lämmin, siksi nukun hyvin (“therefore”), or … niinpä nukun hyvin (“thus/so”).

Why isn’t there a subject pronoun before nukun?

Finnish verbs carry person endings, so the subject is clear from the verb. Nukun already means “I sleep.” You add the pronoun for emphasis or contrast: Minä nukun (I, as opposed to someone else, sleep).

How is nukkua (“to sleep”) conjugated in the present tense?

Type 1 verb; present indicative:

minä nukun
sinä nukut
hän/se nukkuu
me nukumme
te nukutte
he/ne nukkuvat

How do I say this in the past or negate it?

Simple past (imperfect): Nukuin hyvin (“I slept well”).
Negative present: En nuku hyvin (not “En nukun”).
Negative past: En nukkunut hyvin.
Present perfect: Olen nukkunut hyvin.

Why hyvin and not hyvä or hyvää?

Hyvin is the adverb “well.” Hyvä is the adjective “good,” and hyvää is its partitive form (used in other structures, e.g., Hyvää yötä). Don’t use hyvästi here—that means “farewell.”

Why is it lämmin and not lämmintä?

With a countable singular subject like peitto, the predicative adjective is in the nominative: Peitto on lämmin. The partitive predicative (e.g., lämmintä) is used with mass nouns: Maito on lämmintä (“Milk is warm”).

If the subject were plural, how would the adjective behave?

Two options, with a nuance:

Descriptive quality: Peitot ovat lämpimiä (“The blankets are warm.”).
Identifying/total: Peitot ovat lämpimät (“The blankets are the warm ones.”).

Could I use kuuma instead of lämmin?

You can, but it changes the meaning. Lämmin = warm (pleasant); kuuma = hot (possibly too hot). Peitto on kuuma would suggest it’s overly hot/heated.

What are the forms of olla (“to be”) relevant here?

Present indicative:

minä olen
sinä olet
hän/se on
me olemme
te olette
he/ne ovat We use on because the subject (peitto) is 3rd person singular.

How flexible is the word order in the second clause?

Neutral is nukun hyvin. You can front the adverb for emphasis: Hyvin nukun (I sleep well, indeed). The verb still stays in second position commonly in speech, but Finnish allows focus-driven fronting.

Does peitto mean “the blanket” or “a blanket”?

Finnish has no articles; context supplies definiteness. Peitto can mean “the blanket” or “a blanket.” If you need to be explicit:

“the blanket” ≈ se peitto
“a blanket” ≈ yksi peitto (rare; usually context is enough)

How do I say “my blanket is warm, so I sleep well”?

Use a possessive suffix: Peittoni on lämmin, joten nukun hyvin. You can add the pronoun for emphasis: Minun peittoni on lämmin…

Any pronunciation tips for this sentence?

Stress the first syllable of each word: PEI-tto | on | LÄM-min | JO-ten | NU-kun | HY-vin.
ei in peitto is the diphthong like “ay” in “say,” short; tt is a long, crisp [tː].
ä in lämmin is a front vowel (like the a in “cat,” but pure), and mm is long.
j in joten is like English y in “yes.”
y in hyvin is the rounded front vowel (like German ü/French u).

Can I flip the clauses?

With koska, yes: Nukun hyvin, koska peitto on lämmin. With joten, you typically state the cause first: Peitto on lämmin, joten nukun hyvin. Starting a sentence with Joten… without a stated cause is informal and best avoided in careful writing.

Could I add “under the blanket” explicitly?

Yes: Nukun hyvin peiton alla (“I sleep well under the blanket”). You’d usually keep joten if you keep the cause: Peitto on lämmin, joten nukun hyvin peiton alla.