Kerhohuoneessa istumme tänä iltana yhdessä ja juomme kahvia.

Kerhohuoneessa is the form of kerhohuone meaning club room or common room.

The ending -ssa / -ssä is the inessive case, which usually means in or inside something.

• kerhohuone = club room
• kerhohuoneessa = in the club room

So Finnish often uses a case ending where English would use a separate preposition like in.

Finnish often leaves out subject pronouns when the verb already shows who is doing the action.

Here:

• istumme = we sit / we are sitting
• juomme = we drink / we are drinking

Because the -mme ending already means we, the pronoun me is not necessary.

You could say Me istumme..., but it is usually omitted unless you want extra emphasis, such as we as opposed to someone else.

Istumme comes from the verb istua, meaning to sit.

It is in the 1st person plural present tense, so it means:

• we sit
• we are sitting

A very useful pattern is:

• minä istun = I sit
• sinä istut = you sit
• hän istuu = he/she sits
• me istumme = we sit
• te istutte = you plural / you formal sit
• he istuvat = they sit

So -mme is the important ending for we.

The verb juoda (to drink) has a stem change when it is conjugated.

Its present-tense forms are:

• minä juon
• sinä juot
• hän juo
• me juomme
• te juotte
• he juovat

So juomme is simply the correct we form.

This is a normal part of Finnish verb conjugation: many verbs do not keep the dictionary form unchanged when endings are added.

Kahvia is the partitive form of kahvi.

Finnish often uses the partitive for substances, mass nouns, and things that are not seen as a complete, countable whole. Coffee here is understood as some coffee, not one complete coffee as a finished object.

So:

• juomme kahvia = we drink coffee / we are drinking some coffee

If you used kahvi in the nominative here, it would sound wrong in normal Finnish.

This is very common:

• syön leipää = I eat bread
• juon vettä = I drink water
• juomme kahvia = we drink coffee

Tänä iltana is a fixed type of time expression using the essive case.

• tämä = this
• tänä = this, in the essive form
• ilta = evening
• iltana = evening, in the essive form

Together, tänä iltana means this evening or tonight.

Finnish often uses the essive case for expressions of time when something happens:

• tänä aamuna = this morning
• tänä päivänä = nowadays / on this day, depending on context
• ensi viikolla is different, but also a common time expression

So this is something learners usually just memorize as a natural Finnish pattern.

Usually, yes. In many contexts tänä iltana is a natural equivalent of tonight or this evening.

The exact English translation depends on context, but grammatically Finnish is using a time expression rather than a special single word exactly matching English tonight.

So a learner can usually understand tänä iltana as:

• this evening
• tonight

Yhdessä means together.

It is an adverb, so it describes how the action is done. In this sentence, it tells us that the people are sitting and drinking together.

Its position is flexible, but where it appears can affect emphasis a little. In this sentence it sits naturally before ja juomme kahvia and is understood to apply to the whole situation.

Finnish word order is more flexible than English, so yhdessä could appear in other places too, depending on what the speaker wants to emphasize.

Because both verbs have the same subject, Finnish does not need to repeat anything.

The structure is simply:

• Kerhohuoneessa = in the club room
• istumme = we sit
• tänä iltana = this evening
• yhdessä = together
• ja = and
• juomme kahvia = we drink coffee

Since istumme and juomme are both clearly we forms, the sentence is perfectly clear without adding me.

English does the same thing in a way:

• We sit and drink coffee not
• We sit and we drink coffee unless you want special emphasis

Finnish word order is quite flexible because case endings and verb endings carry a lot of grammatical information.

A more English-like order might be something like:

• Istumme kerhohuoneessa tänä iltana yhdessä ja juomme kahvia.

But starting with Kerhohuoneessa puts the location first and gives it a bit of focus. It can feel like:

• In the club room, we are sitting together tonight and drinking coffee.

So the sentence is not strange; it simply reflects Finnish flexibility and emphasis.

Yes, often it could.

For example:

• Istumme kerhohuoneessa tänä iltana yhdessä ja juomme kahvia.
• Tänä iltana istumme kerhohuoneessa yhdessä ja juomme kahvia.

These all keep the basic meaning, but the first word often gets extra emphasis or sets the scene.

So in Finnish, changing word order does not always change the core meaning, but it often changes focus, style, or what sounds most important.

Finnish does not have articles like English a/an and the.

That means words like kerhohuoneessa and kahvia do not contain a separate word for the or a. The listener understands from context whether something is definite, indefinite, known, general, and so on.

So:

• kerhohuoneessa can mean in the club room or in a club room, depending on context
• kahvia can mean coffee or some coffee

This is very normal in Finnish and something English speakers need to get used to.

This is the difference between location and movement into a place.

• kerhohuoneessa = in the club room
  This tells where someone is.
• kerhohuoneeseen = into the club room
  This tells movement toward the inside of the room.

So:

• Istumme kerhohuoneessa. = We are sitting in the club room.
• Menemme kerhohuoneeseen. = We go into the club room.

This inside-location vs inside-motion contrast is very important in Finnish.

It can do either, depending on context.

Finnish present tense often covers both:

• we sit / we drink
  and
• we are sitting / we are drinking

In this sentence, because of tänä iltana (this evening / tonight), it sounds like a situation happening in this specific time frame, so English may naturally translate it with a progressive form:

• We are sitting ... and drinking coffee

But grammatically Finnish just uses the present tense.

In this sentence it is most naturally understood to apply to the whole situation: the people are together, sitting and drinking coffee together.

In real language, adverbs can sometimes attach more strongly to one part of a sentence than another, but here the natural reading is broad and simple: the group is together for the whole event.

Yes. Finnish uses compound words very often.

• kerho = club
• huone = room
• kerhohuone = club room

Then the case ending is added to the whole compound:

• kerhohuoneessa = in the club room

This is very typical Finnish word-building, and recognizing compounds is a big help when reading.