Keskiviikkoisin opiskelen suomea kirjastossa.

On Wednesdays I study Finnish in the library.

Breakdown of Keskiviikkoisin opiskelen suomea kirjastossa.

• minä: I
• suomi: Finnish
• -ssa: in
• opiskella: to study
• kirjasto: the library
• keskiviikkoisin: on Wednesdays

Questions & Answers about Keskiviikkoisin opiskelen suomea kirjastossa.

Why is it keskiviikkoisin and not keskiviikkona?

Keskiviikkona means on (a) Wednesday, usually one specific Wednesday:

• Keskiviikkona menen lääkäriin. = I’m going to the doctor on Wednesday (this particular Wednesday).

Keskiviikkoisin means on Wednesdays (regularly, every Wednesday):

• Keskiviikkoisin opiskelen suomea. = I study Finnish on Wednesdays (as a habit).

So:

• keskiviikkona → one particular Wednesday
• keskiviikkoisin → all/any Wednesdays as a repeated routine

What exactly is the ending -isin in keskiviikkoisin?

Historically, -isin is an old plural case ending (the instructive plural), but in modern Finnish you can simply think of it as a special adverbial ending that:

• attaches mainly to time words
• gives the meaning “on Xs / every X / regularly on X”

Common examples:

• maanantaisin – on Mondays
• tiistaisin – on Tuesdays
• keskiviikkoisin – on Wednesdays
• iltaisin – in the evenings
• aamuisin – in the mornings

You do not need to use -isin productively on all nouns; just learn it with the common time expressions where it appears.

Why is it opiskelen and not minä opiskelen?

The subject I is already contained in the verb ending -n in opiskelen, so the pronoun minä is not required.

• opiskelen = I study / I am studying
  
  • stem: opiskele-
  • ending -n = 1st person singular

In Finnish, subject pronouns (minä, sinä, hän, etc.) are usually left out unless you want to emphasise or contrast:

• Opiskelen suomea. = I study Finnish. (neutral)
• Minä opiskelen suomea, en ruotsia. = I study Finnish, not Swedish. (contrast/emphasis)

So minä opiskelen suomea kirjastossa is grammatically correct, but in neutral everyday speech you normally just say opiskelen suomea kirjastossa.

What tense is opiskelen, and how does it compare to English “I study / I am studying”?

Opiskelen is in the present tense. Finnish has only one present tense form, and it covers both:

• English present simple:
  
  • Opiskelen suomea. = I study Finnish.
• English present continuous:
  
  • Opiskelen suomea nyt. = I am studying Finnish now.

In the sentence Keskiviikkoisin opiskelen suomea kirjastossa, the time expression keskiviikkoisin shows this is a habitual action → “I (normally) study Finnish at the library on Wednesdays.”

Why is it suomea and not suomi?

Suomea is the partitive form of suomi (Finnish), and here it is used as the object of the verb opiskella.

Finnish often uses the partitive as the object when:

• the action is ongoing, incomplete or unbounded
• you are talking about learning, knowing, speaking some of a language / some of a subject

That is why you normally say:

• opiskelen suomea – I study Finnish
• puhun suomea – I speak Finnish
• opin suomea – I am learning Finnish

Suomi (nominative) would be wrong here as an object. The correct form after opiskella in this meaning is suomea.

What case is suomea, and when is that case used?

Suomea is partitive singular of suomi.

The partitive (here -a) has several important uses. Some relevant ones:

1. Object of certain verbs, including:

   • verbs of speaking, studying, learning, understanding languages:
     
     • puhua suomea, opiskella suomea, oppia suomea, ymmärtää suomea
   • verbs of liking, loving, fearing:
     
     • rakastan sinua, pelkään pimeää

2. Ongoing or incomplete actions:

   • Luemme kirjaa. – We are (in the process of) reading a book.

3. Indefinite or uncountable amount:

   • Juon vettä. – I drink (some) water.
   • Syön omenaa. – I am eating (some) apple.

In opiskelen suomea, you are engaged in the ongoing activity of studying Finnish, not “finishing” it as a whole, so the partitive is natural.

Could I also say opiskelen suomen kieltä instead of opiskelen suomea?

Yes, you can, and it is grammatically correct:

• Opiskelen suomea.
• Opiskelen suomen kieltä.

Both mean I study Finnish, but there is a small nuance:

• suomea – the most common, neutral and everyday way to say “Finnish (the language)” in this context.
• suomen kieltä – literally “the Finnish language”.
  
  • suomen = genitive of suomi (of Finnish)
  • kieltä = partitive of kieli (language)

Suomen kieltä can sound a bit more explicit / formal / school-like, but in practice both are fine. In normal conversation you will hear opiskelen suomea more often.

Why is it kirjastossa and not just kirjasto?

Kirjastossa is the inessive case of kirjasto and means “in the library / at the library.”

• kirjasto (nominative) = a library / the library
• kirjastossa (inessive) = in / at the library

Finnish usually expresses location and movement with case endings, not with separate prepositions like English in, at, to, from. So:

• Olen kirjastossa. = I am in/at the library.
• Tapaan hänet kirjastossa. = I’ll meet her/him at the library.

Using bare kirjasto after opiskelen would be ungrammatical for this “at/in” meaning; you need kirjastossa to mark the location.

What case is kirjastossa, and how does it compare to other location cases?

Kirjastossa is inessive case: “inside / in / at the library”.

Finnish has three very common interior location cases:

1. Inessive (-ssa / -ssä) – in / inside / at

   • kirjastossa – in the library

2. Illative (-Vn / -seen / -hVn, here -oon) – into

   • kirjastoon – into the library / to the library

3. Elative (-sta / -stä) – out of / from inside

   • kirjastosta – out of / from the library

Examples:

• Olen kirjastossa. – I am in the library.
• Menen kirjastoon. – I go to (into) the library.
• Tulen kirjastosta. – I come from the library.

In the original sentence, the action is happening in a place (not going to or from it), so the inessive kirjastossa is used.

Can the word order be changed, for example to Kirjastossa opiskelen suomea keskiviikkoisin?

Yes. Finnish word order is fairly flexible, and all of the following are grammatical:

• Keskiviikkoisin opiskelen suomea kirjastossa.
• Opiskelen suomea kirjastossa keskiviikkoisin.
• Kirjastossa opiskelen suomea keskiviikkoisin.
• Suomea opiskelen kirjastossa keskiviikkoisin.

However, moving elements around changes emphasis and what is “old” vs. “new” information:

• Starting with keskiviikkoisin puts time in focus: It’s on Wednesdays that I do this.
• Starting with kirjastossa highlights place: At the library, I study Finnish on Wednesdays (as opposed to somewhere else).
• Starting with suomea highlights what you study: Finnish is what I study…

The original order Keskiviikkoisin opiskelen suomea kirjastossa is a natural, fairly neutral way to say this.

Is there anything special about the vowel changes like suomi → suomea or kirjasto → kirjastossa?

Yes, there are two common patterns here:

1. Stem change: suomi → suome-

   For many -i ending nouns, the i changes to e before certain endings:

   • suomi → suomea (partitive)
   • suomi → suomen (genitive)

   Similar patterns:

   • järvi → järveä, järven
   • kieli → kieltä, kielen

   So the base for case endings is often the stem (suome-), not the nominative form suomi.

2. Vowel harmony in -ssa / -ssä:

   The inessive ending is -ssa or -ssä, depending on the vowel harmony of the word:

   • kirjasto → kirjastossa (back vowels a, o → -ssa)
   • kylä → kylässä (front vowel ä → -ssä)

   Words with only front vowels (ä, ö, y) take -ssä, words with any back vowel (a, o, u) take -ssa (plus some mixed-vowel details).

So:

• suomi → suomea: stem change i → e plus partitive -a
• kirjasto → kirjastossa: inessive -ssa chosen by vowel harmony.