Minä opin uusia sanoja kuuntelemalla jalkapallo-ottelua suomeksi.

Oppia means “to learn, to come to know” (to acquire new knowledge/skills).
Opiskella means “to study” (to engage in studying, but not necessarily to succeed).
Opetella means “to practice/learn (a skill)”, often something practical or specific (e.g. opetella ajamaan – to learn to drive).

So:

• Minä opin uusia sanoja = I (actually) learn new words / I pick up new words.
• Minä opiskelen suomea = I study Finnish.
• Minä opettelen uusia sanoja = I’m actively practicing/trying to learn new words.

In this sentence, opin is natural because you are emphasizing the result: that you do indeed learn new words by listening.

Opin is the present tense of oppia, 1st person singular.

Finnish doesn’t have a separate continuous tense like English.
The Finnish present tense covers both:

• I learn new words…
• I am learning new words…

So Minä opin uusia sanoja… can be translated as either I learn new words… or I am learning new words…, depending on context.

Uusia sanoja is partitive plural, while uudet sanat is nominative plural.

• uusia sanoja (partitive plural) is used because:

  • You’re learning an indefinite, open-ended amount of words.
  • The result is not a clearly limited set; you’re just picking up “some new words.”

• uudet sanat (nominative plural) would refer to a specific, complete set of words:

  • Opin uudet sanat. = I learned the new words (all of them from some known list).

In the sentence, you’re talking about learning some new words in general, so uusia sanoja (partitive) is correct and natural.

In Finnish, the adjective agrees with the noun in case and number.

• Noun: sanoja (partitive plural of sanat)
• Adjective: uusia (partitive plural of uudet)

So you must say:

• uusia sanoja = new (some) words
  Not: uusia sanat (wrong, mismatch of cases)

Adjective–noun agreement is very strict: if the noun is partitive plural, the adjective modifying it must also be partitive plural.

Kuuntelemalla comes from the verb kuunnella (to listen), whose present stem is kuuntele-.

It is the third infinitive, adessive case (sometimes called the “-malla/-mällä form”), and it means “by (doing) X”.

Formation pattern:

• Verb stem + -ma/-mä
  • -lla/-llä
    
    • kuuntele-
      • -ma
        • -lla → kuuntelemalla
    • lukea → lukemalla (by reading)
    • puhua → puhumalla (by speaking)

So kuuntelemalla = by listening.

Yes. Kuuntelemalla functions as an adverbial of manner/means: it tells how / by what means you learn new words.

• Minä opin uusia sanoja kuuntelemalla…
  = I learn new words *by listening…*

This third infinitive in -malla/-mällä is very common to express “by doing” something in Finnish.

Jalkapallo-ottelua is in the partitive singular.

The verb kuunnella (to listen to) usually takes its object in the partitive when the action is:

• ongoing,
• unbounded, or
• not about completing the whole thing.

Here you’re just listening (in general) to a football match, not focusing on having listened to the entire match as a completed whole. So:

• kuunnella jalkapallo-ottelua = listen to (a) football match (ongoing)
• kuunnella jalkapallo-ottelun would sound like focusing on the entire match as a bounded object, and is less natural in this context.

So jalkapallo-ottelua matches the typical pattern kuunnella + partitive object.

Jalkapallo-ottelua is partitive singular.

Formation:

• Nominative singular: jalkapallo-ottelu (football match)
• Stem for case forms: jalkapallo-ottelu-
• Partitive singular ending: -a / -ä
  → jalkapallo-ottelua

So: jalkapallo-ottelu → jalkapallo-ottelua (partitive singular).

Jalkapallo-ottelu is a compound noun:

• jalkapallo = football (lit. “foot-ball”)
• ottelu = match

When one part of a compound is itself a multi-part word (like jalkapallo), Finnish often uses a hyphen to make the structure clearer.

So instead of jalkapalloottelu (which is hard to parse), you get jalkapallo-ottelu, clearly showing: football + match.

Suomeksi is the translative case of suomi, and it’s used to mean “in Finnish / in the Finnish language”.

• suomeksi = in Finnish (as a language)
• suomessa (inessive) = in Finland (the country)
• suomea (partitive) = Finnish (as an object, e.g. puhun suomea – I speak Finnish)

To say something happens in a certain language, Finnish uses the -ksi form:

• suomeksi – in Finnish
• englanniksi – in English
• ruotsiksi – in Swedish

So jalkapallo-ottelua suomeksi = a football match in Finnish.

Yes. In Finnish, the personal ending on the verb (-n in opin) usually shows the subject clearly, so the pronoun minä is often optional.

• Minä opin uusia sanoja…
• Opin uusia sanoja…

Both are correct. Including minä can add a slight emphasis on I (as opposed to someone else), or just sound a bit more explicit, but grammatically it’s not required.

Finnish word order is fairly flexible, but the neutral and most natural order in this sentence is:

• Minä opin uusia sanoja kuuntelemalla jalkapallo-ottelua suomeksi.

Moving uusia sanoja to the end (…suomeksi uusia sanoja) is technically possible, but sounds marked and slightly awkward here. It might put extra focus on uusia sanoja, as if contrasting it with something else.

For everyday, neutral speech, keep:

• Subject + verb + uusia sanoja (object) + kuuntelemalla jalkapallo-ottelua suomeksi (adverbial).

Yes, you can.

• suomeksi = in Finnish (adverbial: the language used)
• suomenkielistä jalkapallo-ottelua = a Finnish-language football match (adjective + noun phrase, partitive)

So:

• kuuntelemalla jalkapallo-ottelua suomeksi
• kuuntelemalla suomenkielistä jalkapallo-ottelua

Both mean almost the same thing: you are listening to a football match in Finnish. The original is a bit shorter and more colloquial; the suomenkielistä version explicitly labels the match as “Finnish-language.”