Learn Hardcore Finnish: Avaan verhot aamulla, jotta huoneeseen tulee valoa. - I open the curtains in the morning so that light comes into the room.

Avata is the basic form (the infinitive) meaning to open.
In a real sentence you normally need a conjugated verb that shows the subject and tense.

Verb: avata (to open)
Stem: avaa-
1st person singular ending: -n

So:

avaan = I open

Finnish usually drops the pronoun minä because the -n ending already shows that the subject is I.
So Avaan verhot literally is (I) open the curtains.

Why is there no word for “I” in Avaan verhot?

Finnish verb endings show the person, so the subject pronoun is often unnecessary:

avaan – I open
avaat – you (sing.) open
avaa – he/she/it opens
avaamme – we open
avaatte – you (pl.) open
avaavat – they open

Because avaan already clearly means I open, the pronoun minä is usually left out:

Minä avaan verhot – correct, but adds emphasis to I
Avaan verhot – normal, neutral sentence

What tense is avaan? Does it mean “I open” or “I will open”?

Avaan is in the present tense.

In Finnish, the present tense is used for:

Current actions / general truths
- Avaan verhot – I am opening / I open the curtains.
Regular / habitual actions
- Avaan verhot aamulla – I open the curtains in the morning (as a habit).
Future actions (when context is clear)
- Huomenna avaan verhot aikaisin – Tomorrow I will open the curtains early.

So in this sentence it can be understood as a habitual action (what you normally do) or as something you do whenever that situation happens, both covered by the Finnish present tense.

Why is it verhot and not verho?

Verho means a curtain, singular.
Verhot means curtains, plural.

In most homes there are two curtains or more at a window, so Finnish normally talks about them in the plural:

Avaan verhon – I open the curtain (one curtain)
Avaan verhot – I open the curtains (the set of curtains)

Here verhot is the object of avaan, in plural nominative form, referring to all the curtains you open.

Why is it verhot (nominative plural) and not something like verhoja?

Finnish treats objects differently depending on whether the action is seen as complete/total or partial/ongoing.

Avaan verhot.
– I open the curtains (completely; the whole set).
Object: total object, so plural nominative: verhot.
Avasin verhoja.
– I was (in the process of) opening some curtains / I opened curtains (but not necessarily all).
Object: partitive plural: verhoja, indicating an incomplete or indefinite amount.

In your sentence, you are opening the curtains fully as a whole action, so verhot (total object) is the natural choice.

What does aamulla mean literally, and why does it end with -lla?

Aamulla comes from aamu (morning) + -lla, which is the adessive case.

Literally, aamulla means on the morning, but in natural English it’s in the morning.

Finnish often uses -lla/-llä with time expressions to mean at / in a part of the day:

aamulla – in the morning
päivällä – in the daytime / in the afternoon
illalla – in the evening
yöllä – at night

So Avaan verhot aamulla = I open the curtains in the morning.

Why is there a comma before jotta?

In Finnish, you normally put a comma before a conjunction that starts a new clause, including jotta.

Avaan verhot aamulla, jotta huoneeseen tulee valoa.
– Main clause: Avaan verhot aamulla
– Subordinate (purpose) clause: jotta huoneeseen tulee valoa

Even though modern English often omits a comma before so that, Finnish usually keeps the comma before jotta.

What does jotta mean exactly, and how is it different from että or koska?

Jotta introduces a purpose clause – it means so that / in order that.

Avaan verhot aamulla, jotta huoneeseen tulee valoa.
– I open the curtains in the morning so that light comes into the room.

Compare with:

että – that / so that, but usually for results or reported speech, not purpose:
- Olen iloinen, että huoneeseen tulee valoa.
  – I’m happy that light comes into the room.
koska – because, gives a reason:
- Avaan verhot aamulla, koska haluan valoa huoneeseen.
  – I open the curtains in the morning because I want light in the room.

So:

jotta = for the purpose that / in order that
että = that (content/result)
koska = because (reason)

Why is it huoneeseen and not just huone?

Huoneeseen is the illative case, which often means into a place.

Nominative: huone – room
Illative: huoneeseen – into the room

Finnish usually marks the direction of movement with cases instead of separate prepositions:

huoneeseen – into the room
huoneessa – in the room
huoneesta – out of the room

Because light is coming into the room, you use the illative:

huoneeseen tulee valoa – (into-)the-room comes light

Why does huoneeseen become huoneeseen (with -seen) instead of something like huoneen?

Words ending in -e often get -eseen in the illative:

huone → huoneeseen (into the room)
perhe → perheeseen (into the family)
kirje → kirjeeseen (into the letter)

By contrast, huoneen is the genitive form:

huoneen ikkuna – the room’s window / the window of the room

So:

huoneeseen = into the room (direction)
huoneen = of the room (possession)

Why is it tulee valoa and not on valoa or tulee valo?

Tulla means to come, so tulee valoa literally means (there) comes light.

huoneeseen tulee valoa – light comes into the room
(focus on the light entering)
huoneessa on valoa – there is light in the room
(focus on the state of there being light)

The choice between valoa and valo:

tulee valoa – some light comes; indefinite amount, general brightness
tulee valo – a specific light comes (for example, a particular lamp turning on)
This sounds unusual in this general, natural-light context.

So tulee valoa is natural here because it describes some amount of light entering the room.

Why is valo in the form valoa?

Valoa is the partitive singular of valo (light).

Finnish uses the partitive in several situations; here the key idea is indefinite quantity / “some” of something:

juon vettä – I drink (some) water
syön leipää – I eat (some) bread
huoneeseen tulee valoa – (some) light comes into the room

Using the nominative valo would suggest a whole, countable thing:

Huoneeseen tulee valo.
– A (particular) light comes into the room.
Sounds like e.g. “the light (fixture) is coming into the room,” or at least a specific, defined light, which is odd here.

So valoa matches the idea of general, uncountable light.

Can I change the word order in jotta huoneeseen tulee valoa?

Yes, Finnish word order is more flexible than English. You can move elements to change emphasis, not the basic meaning:

jotta huoneeseen tulee valoa – neutral; light comes into the room
jotta valoa tulee huoneeseen – emphasizes valoa (the fact that it’s light that comes)
jotta valoa huoneeseen tulee – strong focus on valoa huoneeseen together

All of these are understandable, but the original order huoneeseen tulee valoa is the most neutral and natural here.