Learn Hardcore Finnish: Kun aurinko laskee, sytytämme lampun terassilla. - When the sun sets, we turn on the lamp on the terrace.

Kun is a subordinating conjunction meaning “when” (not to be confused with the interrogative milloin, which means “when?” as in “at what time?”). In this sentence, Kun introduces a temporal clause, telling us when the action in the main clause will take place.

Why is laskee in the present tense even though the setting of the sun might be in the future?

Finnish often uses the present tense for both habitual and expected future actions. Here, laskee (the present form of laskea, “to set”) can be understood as “sets” or “will set.” There is no separate future tense in Finnish; context (and sometimes words like huomenna “tomorrow”) tells you it’s future.

What is the word order in this sentence, and is it flexible?

The example follows the typical order:
1) Subordinate clause (Kun aurinko laskee,)
2) Main clause (sytytämme lampun terassilla.)
Finnish word order is relatively flexible, but placing the temporal clause first is most natural when you want to emphasize the timing. You could also say Sytytämme lampun terassilla, kun aurinko laskee, though that shifts the focus slightly.

How do we get sytytämme from the infinitive sytyttää?

To form the 1st person plural present:
1) Remove the -tä ending from the infinitive stem (sytyt-)
2) Add the person-marker -mme → sytytämme.
This always gives you “we do X” for most verbs in Finnish.

Why is lampun in the -n form rather than lampu or lamppua?

Lampun is the accusative (sometimes called the “total object”) of lamppu. You use -n here because the action is completed on one specific lamp. If you said lamppua (the partitive), it would sound like an incomplete or ongoing action (“we light up some lamp” without specifying it fully).

What case is terassilla, and what does it tell us?

Terassilla is in the adessive case (marked by -lla / -llä), indicating the location “on the terrace.” The adessive is used for surfaces or general locations, often translating to “on” or “at” in English.

Why isn’t there any article before aurinko, lampun or terassilla?

Finnish has no articles (no words for “a,” “an,” or “the” as separate items). Definiteness or indefiniteness is inferred from context. If you wanted to emphasize a terrace rather than the terrace, you might add adjectives, but you wouldn’t use an article word.

Could we express the same idea with Kun aurinko on laskenut? What’s the nuance?

Yes. Kun aurinko on laskenut uses the perfect tense (“when the sun has set”). That emphasizes that the setting is completed before you light the lamp. With the simple present laskee, it’s more neutral or habitual: “whenever the sun sets….” Both are correct; the perfect version often sounds a bit more formal or specific about sequence.