Learn Hardcore Finnish: Olen äskettäin katsonut videon, jossa professori selittää suomen kielioppia. - I have recently watched a video in which a professor explains Finnish grammar.

katsoin videon = simple past (preterite).
- Neutral past event: “I watched the video.”
olen katsonut videon = present perfect.
- Connects the past event to the present. It often implies:
  - the result is relevant now (e.g. that video is in your mind now), or
  - you’re talking about your experience up to now.

In English:

katsoin videon ≈ I watched the video.
olen katsonut videon ≈ I have watched the video.

Here olen äskettäin katsonut videon highlights recent experience that still feels current.

What exactly is katsonut grammatically?

katsonut is the active past participle of the verb katsoa (to watch).

Stem: katso-
Past participle: katsonut

In compound tenses, Finnish forms the perfect and pluperfect with:

present / past of olla
- past participle

So:

olen katsonut = I have watched (perfect)
olin katsonut = I had watched (pluperfect)

So olen katsonut literally is: “I am (one who has) watched.”

Why is it videon and not video or videota?

videon is the object in the genitive form, which in this context functions as a total object:

videon = the whole video, completely watched

Object case with katsoa:

Katsoin videon. – I watched the (whole) video. (finished)
Katsoin videota. – I was watching (some) video / I watched the video partly / activity-focused, not completed.

In your sentence, videon expresses that you watched the entire video. The perfect olen katsonut does not change that; the object is still a total object, so videon, not videota.

Why is it jossa and not joka? What does jossa mean exactly?

jossa is a form of the relative pronoun joka (which / who / that).

joka behaves like an adjective and takes case endings:

joka – nominative (who/which/that)
jonka – genitive (whose / of which)
jossa – inessive (in which / where)
johon – illative (into which)
etc.

In videon, jossa professori selittää…:

The head noun is videon (video).
The professor is inside the video (figuratively; in the video).
So you need “in which”, not just “which” → jossa.

Literal structure:

videon, jossa professori selittää… = “the video, in which a professor explains…”
English would often just say “a video where / in which…”.

You cannot replace jossa with plain joka here; it would be ungrammatical.

Why is professori selittää in the present tense when the main verb is in the past (perfect)?

Finnish often uses the present tense for things that are true whenever you access them, especially in:

books
videos
recordings
instructions

So:

Olen äskettäin katsonut videon, jossa professori selittää suomen kielioppia.
– The watching happened in the recent past (perfect).
– The explaining in the video is presented as happening in an ongoing, timeless way whenever you watch it, so selittää is present.

You could say selitti, but that would feel more like describing a specific past event in time, rather than what happens “in the video as such”.

Why is it suomen kielioppia and not suomen kielioppi?

kielioppia is in the partitive singular. With verbs like selittää (explain), the object often takes the partitive when:

you’re talking about some amount of a mass-like or abstract thing,
or not all of it,
or it’s more about general activity than a bounded, completed “whole”.

Here:

suomen kielioppi = Finnish grammar (as a “whole system”)
suomen kielioppia = (some) Finnish grammar / grammar in general

professori selittää suomen kielioppia suggests that the professor is explaining aspects of Finnish grammar, not literally the entire possible grammar system. That’s why kielioppia (partitive) is natural here.

What does suomen mean here? Why not just suomi?

suomen is the genitive singular of suomi (Finnish, the Finnish language).

Pattern:

nominative: suomi
genitive: suomen

The phrase suomen kielioppi literally means “Finnish’s grammar” = “the grammar of Finnish”.

So:

suomi = Finnish (as a language)
suomen kielioppi / suomen kielioppia = Finnish grammar (grammar of the Finnish language).

Just suomi kielioppi is ungrammatical; you need the genitive suomen before kielioppi / kielioppia.

Should suomen be capitalized like Suomen here?

No, suomen here should not be capitalized:

suomi (lowercase) = the language Finnish
Suomi (capitalized) = the country Finland

In your sentence, suomen kielioppia is about the language’s grammar, so the correct form is suomen with a lowercase s.

You would use Suomen (capital S) in e.g.:

Suomen historia = the history of Finland (the country)

Why is there no word for “a” or “the” before videon or professori?

Finnish has no articles (a, an, the). Definiteness and indefiniteness are expressed by:

context
word order
sometimes object case (partitive vs total object)
sometimes pronouns (e.g. se for “that / it / the”)

So:

Olen katsonut videon could mean “I watched a video” or “I watched the video” depending on context.
professori selittää could be “a professor explains” or “the professor explains”.

Here, natural English would probably be: “I have recently watched a video in which a professor explains Finnish grammar.”

Can I move äskettäin somewhere else in the sentence, like in English?

Yes, äskettäin (recently) is fairly flexible in position. Some common options:

Olen äskettäin katsonut videon… – neutral, very natural.
Äskettäin olen katsonut videon… – emphasizes “recently” more.
Olen katsonut äskettäin videon… – also possible; focus slightly more on when you watched it than on the verb itself.

All of these are grammatically fine. The default, most neutral position is usually before the main verb complex: Olen äskettäin katsonut…

What does äskettäin mean exactly? How is it different from juuri or vasta?

All three relate to recentness, but with nuances:

äskettäin = recently, not long ago
- fairly neutral; could be hours, days, maybe weeks.
juuri (in time sense) = just, just now
- very recent, almost immediate: a moment ago / just now.
vasta (in time sense) = only just, only recently
- often adds a nuance that it’s later than expected or that it’s still relatively new.

So:

Olen äskettäin katsonut videon… – I watched it fairly recently.
Olen juuri katsonut videon… – I just watched it (very recent).
Olen vasta katsonut videon… – I’ve only just watched it (and it’s still kind of new to me).

Could I instead say Äskettäin katsoin videon, jossa…? How does that differ from the original?

Yes, that’s correct Finnish, but with slightly different nuance:

Olen äskettäin katsonut videon…
- present perfect: connects the viewing to the present; sounds a bit more conversational and experience-focused.
Äskettäin katsoin videon…
- simple past: just places the event in the past; a bit more narrative, detached from the present.

Both can translate as “I recently watched a video…” in English. The original with olen katsonut highlights your recent experience more.

Why is it kielioppia and not something like kielioppin to show “of grammar”?

The “of X” relationship is already shown by suomen:

suomen = genitive of suomi = of Finnish
kielioppi / kielioppia = grammar (base noun in nominative or partitive)

So the structure is:

suomen (of Finnish) + kielioppia (grammar, in partitive as the object of selittää)

You do not put kielioppi into genitive here because it’s not “grammar of something else” – Finnish already modifies it. Instead, case on kielioppi / kielioppia is determined by its role as object:

nominative: kielioppi – e.g. as a subject: Suomen kielioppi on vaikea.
partitive: kielioppia – as a partitive object: selittää suomen kielioppia.

Why is professori in basic form and not something like professorin or professoria?

In jossa professori selittää…, professori is the subject of the verb selittää inside the relative clause.

Subjects normally appear in nominative (basic) form: kuka? mikä? → professori.
professorin (genitive) would mean “of the professor”, used for possession.
professoria (partitive) would be used for an object or in some special subject-like structures, not here.

So professori selittää is simply “a/the professor explains”.

Is videon, jossa… closer to “a video where…” or “the video where…” in English?

By itself, videon, jossa… can correspond to either “a video in which…” or “the video in which…”. Finnish has no articles, so context decides.

If you already know which video (it’s been mentioned before), English likely needs “the video”.
If you’re introducing it for the first time, English would choose “a video”.

The Finnish structure itself is neutral; the relative clause jossa professori selittää… just specifies which video you mean.