Learn Hardcore Finnish: Me menemme metsään huomenna.

Using me makes the subject a bit more explicit or emphatic, like We (as opposed to someone else) are going…, but it’s not required for basic grammar.

How is menemme formed, and what are the other forms of mennä in the present tense?

Menemme is the 1st person plural (we) present tense of mennä (to go).

Present tense forms of mennä are:

minä menen = I go / I am going
sinä menet = you (singular) go
hän menee = he / she goes
me menemme = we go
te menette = you (plural) go
he menevät = they go

The ending -mme on mene- tells you the subject is we. Finnish does not add an extra word like will for future; the same forms are used for both present and (contextual) future.

Why is it metsään and not just metsä?

The basic form (dictionary form) is metsä = forest.

In this sentence we need to the forest / into the forest, which in Finnish is expressed with a case ending instead of a separate preposition.

metsä = (a/the) forest (basic form)
metsään = to / into the forest (illative case)

So the ending -än here is the illative case, which usually means movement into or to something. English uses the preposition to; Finnish uses a case ending on the noun.

What is the difference between metsässä and metsään?

They are two different location cases:

metsässä = in the forest (state, no movement)
- Example: Olemme metsässä. = We are in the forest.
metsään = to / into the forest (movement towards/into)
- Example: Menemme metsään. = We are going to the forest.

So you use:

-ssä / -ssä (inessive) for in (static location),
-Vn (here -ään) (illative) for into / to (movement).

Why is there no word like to before metsään? In English we say “to the forest”.

Finnish usually does not use separate words like to, in, on in the same way English does. Instead, those meanings are built into the noun by case endings.

Here:

English: to the forest → preposition to
- noun phrase.
Finnish: metsään → noun metsä
- illative ending -än, which already means to / into.

So metsään alone expresses the idea of to/into the forest; adding a separate word for to is not needed and would be incorrect in standard Finnish.

How do we know this sentence talks about the future (“tomorrow”) if the verb form is just present tense?

Finnish does not have a separate future tense. The present tense verb is used for:

actions happening now, and
future actions, when the context or a time word makes it clear.

In Me menemme metsään huomenna, the word huomenna (tomorrow) tells us that the going happens in the future. So:

Me menemme metsään. = We are going (now / in general).
Me menemme metsään huomenna. = We will go / we are going to the forest tomorrow.

If you want to stress intention, you can add another verb, for example Aiomme mennä metsään huomenna. = We intend to go to the forest tomorrow.

Where can huomenna go in the sentence? Can we move it around?

Yes, Finnish word order is quite flexible, and huomenna (tomorrow) can move without changing the basic meaning. Some common options:

Me menemme metsään huomenna. (very common, neutral)
Me menemme huomenna metsään.
Huomenna me menemme metsään.
Huomenna menemme metsään.

All of these can mean We are going to the forest tomorrow.

Changing the order mainly affects emphasis or what feels like the “topic” of the sentence. For example, starting with Huomenna emphasizes the time (Tomorrow, we are going…).

Does me mean the same as English “me”?

No. This is an easy point of confusion.

Finnish me = English we (1st person plural subject pronoun)
English me = object form of I, which in Finnish is minua (depending on context/case)

Finnish personal pronouns in the basic form (nominative) are:

minä = I
sinä = you (singular)
hän = he / she
me = we
te = you (plural)
he = they

How do you pronounce metsään, and what is the difference between a and ä here?

Pronunciation points:

ä is a front vowel, somewhat like the a in English “cat”, but held a bit longer and more clearly.
aa / ää means the vowel is long. In metsään, the ää is a long ä sound.

So:

metsä roughly like “met-sa” (with ä as in “cat”).
metsään like “met-sää[n]”, with a noticeably longer ä sound at the end.

Vowel length (ä vs ää) is important in Finnish; it can change the meaning of words, so it’s good to pay attention to it early on.

Is it also possible to say Me mennään metsään huomenna, and what is the difference from Me menemme metsään huomenna?

Yes, you will often hear Me mennään metsään huomenna in spoken Finnish, but this is colloquial (puhekieli), not standard written Finnish.

Me menemme… = standard, schoolbook Finnish.
Me mennään… = common spoken Finnish; it uses the so‑called passive form mennään, but with me it functions as we go in everyday speech.

So:

In writing and in formal situations, you should use Me menemme metsään huomenna.
In everyday conversation, Me mennään metsään huomenna. is very natural and widely used. Finnish people will say it all the time.

Why is there no word for “the” before metsään? Is it “to a forest” or “to the forest”?

Finnish has no articles like a / an / the at all.

metsään can be translated as to a forest or to the forest, depending on context.
The Finnish sentence Me menemme metsään huomenna. is neutral; it does not specify whether the forest is already known to the listener or not.

When translating, English must choose a or the, but Finnish does not mark that difference. Context and shared knowledge between speakers decide whether you understand it as a forest or the forest.