Learn Hardcore Finnish: Luen muistiinpanot läpi ennen koetta ja kerron ääneen, mitä ymmärrän. - I read through the notes before the exam and say aloud what I understand.

You don’t normally need a separate future tense (there isn’t one in standard Finnish). The time expression ennen koetta (“before the exam”) already makes it clear that this is about the future, so luen (present) is natural and correct.

Why is it muistiinpanot and not a singular like muistiinpano?

Muistiinpano = “a note”
Muistiinpanot = “notes”

In real use, people nearly always talk about notes in the plural, just like in English:

Luen muistiinpanot läpi. = I read (all) the notes through.

Also, grammatically, muistiinpanot here is:

nominative plural, functioning as the total object of luen.
You are reading all the notes, from beginning to end (completed action).

Compare:

Luen muistiinpanoja.
– partitive plural, implying I’m reading (some) notes / I’m reading notes (ongoing, not necessarily all of them).

So muistiinpanot matches the idea of thoroughly going through the whole set of notes.

What exactly does läpi do here, and how is luen muistiinpanot different from luen muistiinpanot läpi?

Läpi literally means “through”. With verbs of reading, looking, etc., it adds the idea of doing something from start to finish or thoroughly.

Luen muistiinpanot.
= I read the notes. (neutral; could be partial or total, context decides)
Luen muistiinpanot läpi.
= I read the notes through / all the way through.

So läpi emphasizes completeness and thoroughness. It’s a separate word (an adverb/postposition-like element) that combines with the verb phrase.

Why is it ennen koetta and not ennen koe?

The word ennen (“before”) always governs the partitive case.

koe = exam, test (nominative)
koetta = exam, test (partitive)

When you say “before X” in Finnish with ennen, X must be in the partitive:

ennen koetta = before the exam
ennen lomaa = before the holiday
ennen lähtöä = before leaving / departure

So the form koetta is required by ennen, not by the meaning of “exam” itself.

What does ääneen literally mean, and why is that used for “out loud”?

The noun:

ääni = “voice, sound”

Its illative (into/onto) singular form is:

ääneen ≈ “into (the) voice/sound”

Finnish uses ääneen idiomatically with verbs of speaking or thinking to mean “out loud, aloud”:

puhua ääneen = to speak out loud
ajatella ääneen = to think out loud
lukea ääneen = to read out loud
kertoa ääneen = to tell (something) out loud

So kerron ääneen literally is “I tell into (my) voice”, but the idiomatic meaning is “I say it out loud.”

Why is there a comma before mitä ymmärrän?

In Finnish, you normally put a comma before most subordinate clauses, including ones starting with:

että, joka, mikä, kun, koska, jos, vaikka, etc.

Here mitä ymmärrän is a clause that functions like “what I understand”, i.e. it’s a content clause dependent on kerron.

So the structure is:

kerron ääneen, mitä ymmärrän
= “I say out loud what I understand.”

Because mitä ymmärrän is a subordinate clause, you mark its beginning with a comma in standard written Finnish.

Why is it mitä ymmärrän and not mikä ymmärrän?

Both mikä and mitä come from the same base pronoun, but:

mikä = nominative (subject / full object in some contexts)
mitä = partitive (often used as a partial object)

In mitä ymmärrän, the word mitä is the object of the verb ymmärrän (“I understand”). Understanding is typically partial – you understand some things, not necessarily everything. That’s why the partitive is natural:

mitä ymmärrän ≈ “what (things) I understand / whatever I (manage to) understand”

Using mitä here matches the idea that the understanding may be incomplete or limited, which is how Finns usually phrase this kind of sentence.

What exactly does mitä ymmärrän mean in this context?

Literally:

mitä = what (partitive)
ymmärrän = I understand

So mitä ymmärrän = “what I understand (of it) / the parts that I understand”.

In the full sentence:

kerron ääneen, mitä ymmärrän.
= “I say out loud what I understand.”

The idea is: as you read your notes, you verbalize the parts you actually understand, possibly to check or strengthen your understanding.

Could you also say luen läpi muistiinpanot instead of luen muistiinpanot läpi?

Yes, you can. Finnish word order is quite flexible, especially for elements like läpi.

Both are acceptable:

Luen muistiinpanot läpi.
Luen läpi muistiinpanot.

The most common and natural order here is probably muistiinpanot läpi, but luen läpi muistiinpanot is also correct and understandable. The meaning doesn’t really change; it’s more a matter of rhythm and emphasis.

Why is muistiinpanot in the nominative plural and not in the partitive plural muistiinpanoja?

This is about the object type:

muistiinpanot (nominative plural) = total object
muistiinpanoja (partitive plural) = partial / unbounded object

Luen muistiinpanot läpi.

You read all the notes, from beginning to end.
The action is seen as completed with a clear end-point.

Luen muistiinpanoja.

You are reading notes (some notes, or notes in general).
It sounds more like an ongoing activity with no clear limit (“I’m reading notes”).

Because läpi suggests completion (“through”), it naturally goes with the total object muistiinpanot in this sentence.

What is the difference between kerron ääneen and alternatives like sanon ääneen or puhun ääneen?

All are possible, but they have slightly different nuances:

kerron ääneen
– “I tell (it) out loud”;
– suggests that you are explaining or describing something, maybe in a bit more structured way.
sanon ääneen
– “I say (it) out loud”;
– more about simply saying words, maybe shorter expressions or single facts.
puhun ääneen
– “I speak out loud”;
– focuses more on the act of speaking in general, not necessarily conveying a specific piece of information.

In the learning context of the full sentence, kerron ääneen, mitä ymmärrän fits well, because the idea is that you tell/explain to yourself what you have understood from the notes.