Tiistai-iltaisin opiskelen suomea verkossa.

On Tuesday evenings I study Finnish online.

Breakdown of Tiistai-iltaisin opiskelen suomea verkossa.

• suomi: Finnish
• opiskella: to study
• verkossa: online
• tiistai-iltaisin: on Tuesday evenings

Questions & Answers about Tiistai-iltaisin opiskelen suomea verkossa.

What does the ending -iltaisin mean, and why is it used in tiistai-iltaisin?

The ending -isin / -iltaisin / -aamuisin etc. makes a time adverb meaning “on Xs / X-times (habitually)”.

• ilta = evening
• iltaisin = in the evenings (as a regular habit)
• tiistai-ilta = Tuesday evening
• tiistai-iltaisin = on Tuesday evenings (repeated habit)

So tiistai-iltaisin tells us this is something that happens regularly, not just once.

Why do we say tiistai-iltaisin and not tiistai-illat or tiistai-iltoina?

All three are grammatically possible, but they don’t sound the same:

• tiistai-iltaisin = on Tuesday evenings, as a repeated/habitual time (most natural here)
• tiistai-illat = (the) Tuesday evenings (a plural noun phrase, not an adverb).
  You’d normally need something else with it, e.g.
  Tiistai-illat ovat kiireisiä. = Tuesday evenings are busy.
• tiistai-iltoina = on Tuesday evenings (literally “on Tuesday evenings” using the adessive plural).
  This can also express a repeated time, and Tiistai-iltoina opiskelen suomea is correct, but tiistai‑iltaisin is more idiomatic for a regular routine.

So tiistai-iltaisin is chosen because it’s the standard, natural way to say “(regularly) on Tuesday evenings”.

Why is there a hyphen in Tiistai-iltaisin? Is tiistaiiltaisin also correct?

Finnish usually writes compound words together, but it uses a hyphen to avoid awkward letter clusters and to make reading easier.

• Base compound: tiistai-ilta (“Tuesday evening”)
• Adverbial: tiistai-iltaisin

Without the hyphen it would be tiistaiiltaisin, which has the sequence aii in the middle. Official spelling recommendations allow a hyphen in such cases, and tiistai‑iltaisin is the usual, clear form.

So:

• tiistaiiltaisin is technically possible, but
• tiistai-iltaisin is the recommended and much more common spelling.

What form is opiskelen, and why is there no minä?

Opiskelen is:

• Verb: opiskella = to study
• Person/number: 1st person singular
• Tense: present (used for both present and general/habitual actions)

In Finnish, personal endings on the verb show the subject:

• opiskelen = I study
• opiskelet = you study (sg)
• opiskelee = he/she studies

Because -n already tells us it is “I”, the pronoun minä is usually omitted unless you want to emphasize it:

• Opiskelen suomea. = I study Finnish.
• Minä opiskelen suomea. = I (as opposed to someone else) study Finnish.

Why is suomea in this form and not just suomi?

Suomea is the partitive singular of suomi (“Finnish” the language).

Verbs like:

• opiskella (to study)
• puhua (to speak)
• ymmärtää (to understand)
• oppia (to learn)

normally take a language in the partitive case, because the idea is “some Finnish / an unspecified amount of Finnish”, not a clearly finished, bounded object.

Compare:

• Opiskelen suomea. = I study (some) Finnish.
• Puhun suomea. = I speak Finnish.

So suomea is used here because of the verb + language pattern and the unbounded, ongoing nature of studying a language.

What is the difference between suomi, Suomi, and suomea?

They are related but not the same:

• Suomi (capital S)
  = the country, Finland.

  • Pidän Suomesta. = I like Finland.

• suomi (lowercase)
  = the language, Finnish, in its basic (nominative) form.

  • Suomi on vaikea kieli. = Finnish is a difficult language.

• suomea
  = partitive of the language word suomi.

  • Opiskelen suomea. = I study Finnish.
  • Puhun suomea. = I speak Finnish.

In your sentence, suomea is used because it’s the object of “opiskelen” and is treated as “some Finnish” (not a whole, completed object).

What exactly does verkossa mean, and are there other ways to say “online” in Finnish?

Literally:

• verkko = net, network
• verkossa = in the net / in the network

By extension, verkossa means “online, on the internet”.

Common alternatives:

• netissä = on the net (very common, informal-neutral)
• internetissä = on the internet (more explicit, slightly more formal or technical)

All of these are acceptable in everyday language:

• Opiskelen suomea verkossa.
• Opiskelen suomea netissä.
• Opiskelen suomea internetissä.

In your sentence, verkossa just means “online”.

Can the word order be changed, for example to Opiskelen suomea verkossa tiistai-iltaisin? Does that change the meaning?

Yes, Finnish word order is quite flexible. These are all possible:

• Tiistai-iltaisin opiskelen suomea verkossa.
• Opiskelen suomea verkossa tiistai-iltaisin.
• Verkossa opiskelen suomea tiistai-iltaisin.

The basic meaning (I study Finnish online on Tuesday evenings) stays the same.

Word order mainly affects focus/emphasis:

• Starting with Tiistai-iltaisin highlights when it happens.
• Starting with Opiskelen is more neutral and starts with the action.
• Starting with Verkossa emphasizes that it’s online rather than in a classroom.

All are natural; your original version just chooses to highlight the time first.

How would you say “every Tuesday evening I study Finnish online”? Is that different from tiistai-iltaisin?

Two common ways:

1. Tiistai-iltaisin opiskelen suomea verkossa.
   = On Tuesday evenings / (regularly) on Tuesday evenings, I study Finnish online.

2. Joka tiistai-ilta opiskelen suomea verkossa.
   = Every Tuesday evening I study Finnish online.

Both describe a regular weekly habit. The nuance:

• tiistai-iltaisin sounds like a general routine.
• joka tiistai-ilta puts a bit more stress on each individual Tuesday evening (“every single Tuesday evening”).

In most contexts they can translate the same English sentence.

How would you say this sentence in the past tense or to talk about a future plan?

1. Past habitual (used to do this on Tuesday evenings):

• Tiistai-iltaisin opiskelin suomea verkossa.
  = On Tuesday evenings I studied / used to study Finnish online.

Only the verb changes (from opiskelen to opiskelin); the rest stays the same.

2. Future (plan or prediction):

Finnish usually uses the present tense with a future time expression:

• Ensi keväänä tiistai-iltaisin opiskelen suomea verkossa.
  = Next spring, on Tuesday evenings, I will study Finnish online.

Or you can use a more explicitly “future” construction:

• Aion opiskella suomea verkossa tiistai-iltaisin.
  = I am going to study Finnish online on Tuesday evenings.

So tense/future is mostly handled through context words (like ensi keväänä) and sometimes verbs like aikoa (“to intend, to be going to”).