Learn Hardcore Finnish: Jos kuume nousee korkeaksi, menen sairaalaan. - If the fever rises high, I go to the hospital.

present time: Menen nyt sairaalaan. – I’m going to the hospital now.
future time: Menen huomenna sairaalaan. – I will go to the hospital tomorrow.

In conditional sentences like Jos kuume nousee korkeaksi, menen sairaalaan, both verbs are in the present tense, but the whole structure is understood as future:

Jos kuume nousee korkeaksi – If the fever rises (in the future)…
menen sairaalaan – I will go to the hospital.

The future idea comes from context and the word jos (if), not from verb endings.

What exactly does jos mean, and how is it different from kun?

Jos means if, introducing a condition that may or may not happen.

Jos kuume nousee korkeaksi, menen sairaalaan.
If the fever rises high, I’ll go to the hospital.
→ It’s uncertain whether the fever will rise.

Kun usually means when, whenever, or as, and implies something is expected, regular, or factual.

Kun kuume nousee korkeaksi, menen sairaalaan.
When(ever) the fever rises high, I go / I’ll go to the hospital.
→ Suggests a more certain or habitual situation.

So using jos here correctly presents it as a condition, not a sure event.

Why is there no word for "I" in menen sairaalaan? Where is the subject?

Finnish is a pro-drop language: personal pronouns (like minä = I) are often omitted because the verb ending already shows the person.

menen = I go / I will go
menet = you (sg.) go
menee = he/she/it goes
menemme = we go
menette = you (pl.) go
menevät = they go

So:

Menen sairaalaan. = I (will) go to the hospital.
Minä menen sairaalaan. is also correct, but minä is only needed for emphasis or clarity.

In the sentence, I is understood from the form menen.

Why is it kuume nousee korkeaksi instead of just kuume on korkea or kuume nousee korkealle?

The form korkeaksi uses the translative case (-ksi), which often expresses a change of state or becoming something.

korkea – high (basic form)
korkeaksi – to (a) high (state), into being high

So:

kuume on korkea – the fever is high (describes a state)
kuume nousee – the fever rises (the fact of rising)
kuume nousee korkeaksi – the fever rises to a high level (change from lower → high)

The translative -ksi emphasizes the end result of the change: the fever becomes high.

korkealle would be an allative form (to a high place) and sounds more like physical movement upwards (to a high spot), which doesn’t fit as naturally with fever here. For fever levels, korkeaksi (change of state) is the idiomatic choice.

What is the function of the ending -an in sairaalaan?

Sairaalaan is the illative case of sairaala (hospital).

sairaala – a hospital (basic form)
sairaalaan – to (the) hospital

The illative case often expresses movement into something, similar to English to / into:

taloon – into the house
kouluun – to school
Suomeen – to Finland
sairaalaan – to (the) hospital

So menen sairaalaan literally means I go to (the) hospital.

Why is there no article like "a" or "the" before kuume or sairaalaan?

Finnish has no articles (no a/an or the). Concepts like definiteness or indefiniteness are conveyed by context, word order, and sometimes case or demonstratives.

kuume can mean a fever or the fever depending on context.
sairaalaan can mean to a hospital or to the hospital.

In this sentence, natural English translations are:

If the fever rises high, I will go to the hospital.
If my fever gets high, I’ll go to the hospital.

The possessor (my fever) and definiteness (the hospital) are inferred, not spelled out by separate words.

Could I say Menen sairaalaan, jos kuume nousee korkeaksi instead? Does the word order change the meaning?

Yes, both orders are correct:

Jos kuume nousee korkeaksi, menen sairaalaan.
Menen sairaalaan, jos kuume nousee korkeaksi.

The basic meaning is the same: going to the hospital depends on the fever rising high.

The difference is a slight emphasis:

Starting with Jos kuume nousee korkeaksi highlights the condition first.
Starting with Menen sairaalaan highlights the action/decision first, then adds the condition.

In everyday speech and writing, both are natural and commonly used.

Why does kuume behave like the subject here, when in English we say "I have a fever"?

In Finnish, fever is often expressed as something that exists with a person, not as a direct attribute of "me":

Minulla on kuume. – I have a fever. (literally: At me is fever.)

But in Jos kuume nousee korkeaksi, the focus is on the fever itself as something that can rise or fall, so it naturally becomes the grammatical subject:

kuume nousee – the fever rises

It’s similar to English in sentences like:

If the fever rises, I’ll call the doctor.

So even though English often thinks "I have a fever", Finnish comfortably treats kuume as the thing that does the rising.

Can I omit korkeaksi and just say Jos kuume nousee, menen sairaalaan?

Yes, you can say:

Jos kuume nousee, menen sairaalaan.

This is correct and natural. The difference is how specific you are:

Jos kuume nousee – If the fever rises (at all)…
→ Any rise may be enough.
Jos kuume nousee korkeaksi – If the fever rises high…
→ Only if it becomes high, not just a small increase.

Including korkeaksi sets a threshold: you go to the hospital only if the fever becomes high, not for a minor temperature increase.

How is the verb nousta conjugated, and what form is nousee?

Nousta is the basic (infinitive) form meaning to rise / to get up / to increase.

In the sentence, nousee is:

person: 3rd person singular (he/she/it)
tense: present
mood: indicative

Key present tense forms of nousta:

(minä) nousen – I rise
(sinä) nouset – you rise
(hän) nousee – he/she/it rises
(me) nousemme – we rise
(te) nousette – you (pl.) rise
(he) nousevat – they rise

So kuume nousee = the fever rises / will rise.