Learn Hardcore Finnish: Voisitko vastata minulle huomenna?

So voisitko literally means something like “could you / would you be able (to)” and already includes the subject “you” in the verb ending. There is no need to add sinä (you) unless you want to emphasize it.

What does the -ko ending do in voisitko? Is it always attached like that?

-ko / -kö is a question particle used to form yes/no questions in Finnish.

It attaches to the first important word of the clause, often the conjugated verb:
- Voisitko vastata…? = Could you answer…?
- Tuletko huomenna? = Are you coming tomorrow?
It has two forms for vowel harmony:
- -ko after a, o, u
- -kö after ä, ö, y

You don’t write it as a separate word; it is always attached to the preceding word.

Why is the verb in voisitko vastata split like that instead of a single form like vastaisitko?

Finnish often expresses polite requests using voida + infinitive:

Voisitko vastata…?
- voisitko = you could (be able to)
- vastata = to answer (infinitive)

This literally feels like “Could you answer…?” in English and sounds very natural and polite.

You could also say:

Vastaisitko minulle huomenna?
(conditional of vastata itself: Would you answer me tomorrow?)

Both are polite, but:

Voisitko vastata… feels slightly more like “Could you (please) answer…” (emphasis on ability / willingness to do the action).
Vastaisitko… can feel a bit more direct (emphasis on the action itself).

In everyday speech, voisitko + infinitive is extremely common for polite requests.

Why is it vastata and not some other form of the verb?

Vastata is the basic infinitive form (dictionary form) of the verb, meaning to answer.

In the structure voida + infinitive:

The voida part (voisitko) is conjugated (here: conditional, 2nd person).
The main action verb stays in its infinitive form:
- Voisitko tulla? = Could you come?
- Voisitko auttaa? = Could you help?
- Voisitko vastata? = Could you answer?

So vastata is exactly what is expected after voisitko.

Why is it minulle and not minua? What does minulle express?

Minulle literally means “to me”.

minä = I
minulle = to me (allative case: -lle)

The verb vastata is used like this:

vastata jollekin = to answer to someone (allative case)

So you say:

vastata minulle = to answer (to) me
vastata asiakkaalle = to answer (to) the customer

Minua (partitive form) is used in different structures, such as “Minua väsyttää” (I feel tired) or “Minua pelottaa” (I am afraid). With vastata, you need the allative form minulle, not minua.

Can minulle be left out? What changes in meaning if I omit it?

Yes, you can leave out minulle if it is obvious from context whom you want an answer from.

Voisitko vastata huomenna?
= Could you answer tomorrow? (to me, to this message, etc., understood from context)

Including minulle makes it explicit:

Voisitko vastata minulle huomenna?
= Could you answer me tomorrow?

So:

With minulle: explicitly to me.
Without minulle: to someone/something known from context (e.g., an email, a question, a survey).

What does huomenna mean exactly? Is the -na some kind of case ending?

Huomenna means tomorrow.

Historically, it’s related to a case ending, but in modern Finnish you should simply treat huomenna as an adverb of time, like:

eilen = yesterday
tänään = today
huomenna = tomorrow

So for a learner, it’s best not to analyze huomenna as a regular case form (like an essive). Just memorize it as the fixed word for “tomorrow”.

Can the word order change? For example, can I say Voisitko huomenna vastata minulle?

Yes, Finnish allows relatively flexible word order. All of these are grammatically correct:

Voisitko vastata minulle huomenna?
Voisitko vastata huomenna minulle?
Voisitko huomenna vastata minulle?
Huomenna voisitko vastata minulle?

The basic, neutral version is the original:

Voisitko vastata minulle huomenna?

Switching the word order mainly changes emphasis:

Voisitko huomenna vastata minulle?
– A bit more focus on tomorrow (as opposed to some other time).
Huomenna voisitko vastata minulle?
– Strong initial emphasis on tomorrow, almost like: “(As for) tomorrow, could you answer me?”

But in everyday speech, these differences are subtle. All are understood the same way in most contexts.

What is the difference between Voitko vastata minulle huomenna? and Voisitko vastata minulle huomenna?

The difference is mainly in politeness and softness:

Voitko vastata minulle huomenna?
= Can you answer me tomorrow?
– More direct, like asking about ability or availability.
Voisitko vastata minulle huomenna?
= Could you answer me tomorrow?
– More polite/softer, like a polite request.

In everyday interaction:

Voisitko… is the default polite way to ask someone to do something.
Voitko… is not rude, but it’s more direct and can sound a bit more insistent depending on tone and context.

Why isn’t sinä (you) written in the sentence?

In Finnish, the subject pronoun is often dropped because it is already clear from the verb ending.

voisit = you (singular) could
voisitko = could you? (2nd person singular is built into the verb)

So:

Voisitko vastata minulle huomenna?
already clearly means “Could you answer me tomorrow?”

If you add sinä, it adds emphasis:

Voisitko sinä vastata minulle huomenna?
~ Could you (as opposed to someone else) answer me tomorrow?

So the basic, neutral form is without sinä.

Is this sentence formal, informal, or neutral in politeness?

Voisitko vastata minulle huomenna? is polite and neutral, suitable in many situations:

Between friends or colleagues
In relatively polite emails
When you want to be respectful but not overly formal

More formal options might add plural you or extra polite words:

Voisitteko vastata minulle huomenna?
(formal/polite you or addressing several people)
Voisitteko ystävällisesti vastata minulle huomenna?
= Could you kindly answer me tomorrow?

More casual/colloquial could be:

Voitko vastata mulle huomenna?
(mulle = spoken form of minulle)