Learn Hardcore Finnish: Oletko sinäkin hengästynyt, vai oliko hissimatka sinusta liian lyhyt? - Are you also out of breath, or was the elevator ride too short for you?

In Finnish, -ko / -kö is the yes–no question particle.
It usually attaches to the first word of the clause, and that word often ends up being the verb:

olet (you are) → oletko (are you?)
sinä (you) → sinäkö (is it you?)

So oletko literally means “are-you?” and marks the sentence as a question.
Without -ko, Olet sinäkin hengästynyt would be a statement: “You too are out of breath.”

What does sinäkin mean, and how is it different from just sinä?

sinä = you (singular)
-kin is a clitic meaning also, too, as well, even (in some contexts).

So:

sinä = you
sinäkin = you too / you also

In Oletko sinäkin hengästynyt, the -kin shows that someone else is already known or assumed to be out of breath, and the speaker is asking if you as well are out of breath.
It adds the idea of “as well” or “in addition to someone else.”

Why is sinäkin placed after oletko instead of before, like Sinäkin oletko hengästynyt?

In yes–no questions, the verb with -ko/-kö normally comes first:

Oletko sinä väsynyt? – Are you tired?

Putting sinä after oletko is the unmarked, natural order.
Sinäkin oletko hengästynyt is not normal Finnish; it sounds very marked or odd.
If you want to emphasise you more strongly, you can say:

Oletko *sinä*kin hengästynyt?

The basic pattern is: [verb+ko] + [subject/pronoun] + …

What exactly is hengästynyt? Is it a verb, an adjective, or a participle?

Hengästynyt is the past participle (more precisely: the -nut/-nyt active past participle) of the verb hengästyä (to get out of breath, to become breathless).

In practice, participles like this often function as adjectives:

hengästynyt = out of breath, breathless, winded

So in Oletko sinäkin hengästynyt, the structure is just like English “Are you out of breath too?”:

olet (you are) + hengästynyt (out of breath)

Why is vai used here instead of tai?

Both vai and tai can translate as “or”, but:

vai is used in direct questions where you are asking the listener to choose between alternatives.
tai is used in statements and in open / non-exclusive choices.

Here, the speaker gives two contrasting options:

You’re out of breath.
Or was the elevator ride too short for you?

So it is a direct alternative question → vai is the correct conjunction:

Oletko sinäkin hengästynyt, vai oliko hissimatka sinusta liian lyhyt?

Why is it oliko hissimatka and not onko hissimatka?

Onko is present tense (“is / is it?”), oliko is past tense (“was / was it?”).

Hissimatka (the elevator ride) is already over, so Finnish uses the past tense:

oliko hissimatka sinusta liian lyhyt?
→ was the elevator ride too short for you (in your opinion)?

Using onko would suggest the ride is happening now or is somehow current, which does not fit this context.

What does hissimatka mean exactly, and why is it one word?

Hissimatka is a compound noun:

hissi = elevator, lift
matka = trip, journey, ride

Finnish often combines nouns into one word when they form a fixed concept:

bussimatka – bus ride
junamatka – train journey
hissimatka – elevator ride

Writing it as two words (hissi matka) would be incorrect in standard Finnish.

Why is it sinusta and not just sinä or sinulle?

Sinusta is the elative case (“out of / from you”), but here it has an idiomatic meaning: “in your opinion / to you / for you personally.”

This use is common with adjectives that describe how something seems to someone:

Minusta se oli hauska. – I think it was fun.
Sinusta se oli liian lyhyt. – You thought it was too short.

So oliko hissimatka sinusta liian lyhyt? is literally “Was the elevator ride too short from-you?”, meaning:
“Did you feel the elevator ride was too short?” / “In your opinion, was it too short?”

Can sinusta here be replaced with mielestäsi? Is there any difference?

Yes, you can say:

Oliko hissimatka mielestäsi liian lyhyt?

Mielestäsi = “in your opinion” (literally: “from your mind”); it’s slightly more explicit.
Sinusta is a bit shorter and very common in speech; the meaning here is essentially the same.

Stylistically:

sinusta – very natural, neutral, often used in everyday language.
mielestäsi – also common, maybe slightly more “spelled out” as “in your opinion.”

What does liian lyhyt mean, and how is the word order decided?

Liian = too (excessively)
lyhyt = short

So liian lyhyt = too short.

Normal order is:

[noun] + [adjective phrase]
hissimatka liian lyhyt – the elevator ride (was) too short

The adjective phrase liian lyhyt comes after the noun it describes.
Compare:

pitkä matka – a long trip
liian pitkä matka – a too-long trip / a trip that is too long

Could you omit sinä and just say Oletko hengästynytkin or Oletko hengästynyt? Would it mean the same?

Oletko hengästynyt? – Are you out of breath? (no “too/as well” idea)
Oletko hengästynytkin? – grammatically possible, but -kin would then attach to hengästynyt, giving a slightly different nuance (like “Are you actually out of breath?” or “So you’re out of breath after all?” depending on context).

In this sentence, sinäkin is used specifically to mark you as “too / as well”.
Dropping sinä would weaken or change that nuance.
So to clearly express “Are you out of breath too?”, Oletko sinäkin hengästynyt? is the most natural.