Learn Hardcore Finnish: Jos takki on märkä, se pitää ripustaa kuivumaan. - If the coat is wet, it must be hung to dry.

“to like” (e.g. Minä pidän kahvista = “I like coffee”)
“must/have to” when followed by an infinitive verb (e.g. se pitää ripustaa = “it must be hung up”)

Here, the infinitive ripustaa clearly signals the “must” meaning, not “to like.”

How is pitää different from täytyy when talking about what must be done?

Both verbs express necessity, but they behave slightly differently:

pitää is a personal, transitive verb that takes a subject and is followed by the first infinitive (e.g. se pitää ripustaa kuivumaan = “it must be hung up to dry”).
täytyy is impersonal and often used without an explicit subject or with a genitive pronoun (e.g. minun täytyy ripustaa se kuivumaan = “I have to hang it up to dry,” or simply täytyy ripustaa = “must be hung up”).

Stylistically, pitää can feel more colloquial, whereas täytyy may come across as a bit more formal or neutral. In everyday speech, the choice between them is largely a matter of personal or regional preference.

Why is ripustaa in the infinitive form here?

When a verb like pitää (“must”) indicates an obligation, it is followed by another verb in its basic (first) infinitive form to show the action required. The pattern is: subject + pitää + ripustaa (first infinitive)

Thus ripustaa is simply the uninflected “to hang,” specifying what must be done.

What is kuivumaan, and why isn’t it just kuivua?

Kuivumaan is the third infinitive in the illative case. Finnish’s third infinitive (root + -ma/-mä) can take cases to express purpose or direction. The illative ending -maan/-mään means “into doing something.”
So ripustaa kuivumaan literally means “to hang up into drying,” i.e. “to hang up for drying.” Using the first infinitive kuivua alone would only state “to dry” without conveying that you hang it up so it becomes dry.

Do I need the comma after the if-clause with jos?

Yes. In Finnish, it is standard to put a comma between a subordinate clause introduced by jos (“if”) and the main clause. Thus you write: Jos takki on märkä, se pitää ripustaa kuivumaan

Omitting the comma can be acceptable in very short or informal speech, but following the comma rule is the norm.

Why is se used in the second clause, and can it be omitted?

Se is the third-person pronoun referring back to takki. It makes clear that “it” (the jacket) is the subject of pitää ripustaa. In casual spoken Finnish you might drop se and say: Jos takki on märkä, pitää ripustaa kuivumaan but in writing or for clarity you normally keep se so the sentence doesn’t sound abrupt or ambiguous.

Could I use the passive voice instead, for example takki ripustetaan kuivumaan?

Yes—passive constructions are possible:

Takki ripustetaan kuivumaan, jos se on märkä (“The jacket is hung up to dry if it is wet”)
Or the agentless passive with necessity: Takki on ripustettava kuivumaan (“The jacket must be hung up to dry”)

However, using pitää + infinitive (se pitää ripustaa kuivumaan) is more colloquial and directly emphasizes the obligation (“must be hung up”), whereas the passive version can sound more formal or instructional.