Learn Hardcore Finnish: Pimeällä katuvalot auttavat näkemään, minne olen menossa. - In the dark the streetlights help me see where I am going.

Literally, pimeällä is something like “at dark / in the dark (time)”. In practice it works like a time expression meaning “when it is dark / in the dark”.

Finnish often uses the adessive -lla/-llä for times of day and similar “when”-expressions:

yöllä – at night
päivällä – in the daytime
aamulla – in the morning
illalla – in the evening
kesällä – in (the) summer
sateella – when it’s raining

Pimeällä fits this pattern: it describes the general situation or time when something happens: when it’s dark outside.

Could you also say pimeässä instead of pimeällä? Is there a difference?

Yes, you can say pimeässä, but there is a nuance difference.

pimeällä – adessive; focuses on the time / situation
- more like “when it’s dark (outside)”, a general condition
pimeässä – inessive; focuses on being inside the darkness as a kind of space
- more like “in the dark (space)”, surrounded by darkness

In your sentence:

Pimeällä katuvalot auttavat näkemään…
Emphasis: When it’s dark (outside), streetlights help me see…

If you say:

Pimeässä katuvalot auttavat näkemään…
It sounds a bit more like “In the dark, [as an environment], the streetlights help me see…”
Still understandable and not wrong, but pimeällä is the more typical idiomatic choice here, in the same family as yöllä, illalla, sateella.

What exactly is katuvalot and why is it plural?

Katuvalot is a compound noun:

katu – street
valo – light

Combine them and you get katuvalo – streetlight.

Then it’s put in plural nominative:

singular nominative: katuvalo – streetlight
plural nominative: katuvalot – streetlights

In the sentence, katuvalot is the subject of the verb auttavat:

katuvalot auttavat – the streetlights help

It is plural because we naturally think of many streetlights along a street, not just one. The verb auttavat is also plural (3rd person plural) to agree with the plural subject.

Why is it auttavat and not auttaa?

In Finnish, the verb must agree in number with the subject:

singular subject → singular verb
plural subject → plural verb

Here, the subject is katuvalot (plural), so the verb auttaa must be in 3rd person plural:

(yksi) katuvalo auttaa – one streetlight helps
(monet) katuvalot auttavat – many streetlights help

So katuvalot auttavat is the correct agreement.

Why is there no word for “me” in auttavat näkemään, even though in English we say “help me see”?

Finnish doesn’t always need to mention the person being helped when it’s obvious from context.

The full, explicit structure could be:

katuvalot auttavat minua näkemään – the streetlights help me see

But minua (me, in partitive) can be left out if it’s clear that I am the one being helped. The listener understands that auttavat näkemään is helping me (the speaker) see.

So:

katuvalot auttavat näkemään
≈ the streetlights help (me) to see

Omitting the object like this is very common when it is obvious from context.

What form is näkemään, and how is it formed from nähdä?

Näkemään is the illative of the 3rd infinitive of the verb nähdä (to see).

Forms of nähdä relevant here:

basic (1st) infinitive: nähdä – to see
3rd infinitive stem: näkemä-
3rd infinitive illative: näkemään

The ending -mään (or -maan after a back vowel) marks this illative form.

In verbs like this, auttaa + 3rd infinitive illative is a very common pattern:

auttaa näkemään – help (someone) to see
auttaa ymmärtämään – help (someone) to understand
auttaa oppimaan – help (someone) to learn

So näkemään can be thought of as “into the activity of seeing”, but you normally just interpret it as “to see” in English.

What does minne mean, and how is it different from mihin, missä, and mistä?

All of these are question/relative words about place, but they mark different directions:

minne – to where, where to (direction, movement towards something)
mihin – also to what/where, but can be more general (not only physical place)
missä – where, in what place (location, no movement)
mistä – from where, where from (movement away)

In your sentence:

minne olen menossa – where I am going (to)

You could also hear:

mihin olen menossa – very similar in meaning; minne tends to sound a bit more clearly spatial/physical, but in many everyday contexts they are interchangeable.

Summary:

moving towards a place → minne / mihin
staying in a place → missä
moving from a place → mistä

What does the phrase olen menossa mean grammatically? How is it different from just menen?

Menen is the simple present tense of mennä (to go):

menen – I go / I am going

Menossa is a 3rd infinitive inessive form of mennä:

3rd infinitive stem: meno-
inessive: menossa – literally “in (the act of) going”

The structure olla + 3rd infinitive inessive describes being in the middle of doing something:

olen menossa – I am (in the process of) going
olen syömässä – I am eating (lit. “I am in eating”)
olin lukemassa – I was reading

Nuance:

minne menen? – Where am I going? (more neutral “where will I go?”)
minne olen menossa? – Where am I on my way to? (emphasises that I’m already going / on the move)

Your sentence uses minne olen menossa, which fits the idea of “where I’m going (on my way to)” very well.

Could the sentence use minne menen instead of minne olen menossa? What would change?

Yes, grammatically you could say:

Pimeällä katuvalot auttavat näkemään, minne menen.

Both versions are correct, but the nuance is slightly different:

minne menen
- more neutral: “where I go / will go”
- can sound a bit more general or future-like, not necessarily describing being already on the move
minne olen menossa
- “where I am going (right now)” / “where I am on my way to”
- emphasises an ongoing or very near-future movement

In everyday speech, olen menossa is very common when you talk about where you are currently headed.

Why is there a comma before minne olen menossa?

In Finnish, a subordinate clause (a dependent clause) is usually separated from the main clause by a comma.

Here, the main clause is:

Pimeällä katuvalot auttavat näkemään

The part starting with minne is a subordinate clause that functions like an indirect question:

minne olen menossa – where I am going

So the full structure is:

Pimeällä katuvalot auttavat näkemään, minne olen menossa.

The comma marks the boundary between:

main clause: katuvalot auttavat näkemään
subordinate clause: minne olen menossa

This is standard Finnish punctuation and not optional in formal writing.

Why is the word order katuvalot auttavat näkemään and not, for example, katuvalot näkemään auttavat?

Finnish has flexible word order, but there are strong typical patterns.

The basic pattern here is:

adverbial (time): Pimeällä
subject: katuvalot
finite verb: auttavat
non-finite verb complement: näkemään

So:

Pimeällä katuvalot auttavat näkemään…

This order is natural because:

the finite verb (auttavat) normally comes early in the clause, after the subject
the infinitive complement (näkemään) tends to follow the main verb

Something like katuvalot näkemään auttavat would be unusual and feel wrong in normal prose. Finnish does allow some reordering for emphasis, but moving näkemään in front of auttavat here would not be idiomatic.

Could the word order be Pimeällä auttavat katuvalot näkemään? Would that change the meaning?

You could say:

Pimeällä auttavat katuvalot näkemään, minne olen menossa.

This is grammatically possible, but the emphasis changes.

Pimeällä katuvalot auttavat näkemään…
- neutral: subject (katuvalot) right after the time expression
Pimeällä auttavat katuvalot näkemään…
- puts more focus on the verb first (auttavat) and then slightly emphasizes katuvalot as the ones who do the helping

The second version might appear in contexts where you contrast katuvalot with something else:

Pimeällä auttavat katuvalot näkemään, eivät taskulamput.
In the dark, it’s the streetlights that help us see, not flashlights.

So the meaning stays basically the same, but the information structure and emphasis shift.