Learn Hardcore Finnish: Siirsin kirjoituspöydän ikkunan viereen eilen. - I moved the desk next to the window yesterday.

siirsin is the first person singular past tense (preterite) form of the verb siirtää (“to move”). The element -si- marks the past tense and -n marks “I” as the subject.

Why is kirjoituspöydän in this form instead of kirjoituspöytä or kirjoituspöytää?

Here it’s a definite, complete object, so it takes the accusative case. In Finnish the accusative singular of many nouns looks the same as the genitive singular. So kirjoituspöydän indicates “the (specific) writing desk” that was moved.

What case is ikkunan viereen, and why is ikkunan in genitive while viereen has its own ending?

This is a motion‐to location phrase. viereen is the illative case of vieri (“side”), meaning “to the side.” ikkunan is the genitive of ikkuna (“window”), showing whose side it is: “to the window’s side,” i.e. “to beside the window.”

Why not use vieressä instead of viereen?

vieressä is the adessive case, indicating a static location (“beside,” “at the side of”). Because you’re describing movement (“I moved the desk”), you need the illative viereen to show “to beside.”

Why is eilen placed at the end of the sentence, and can its position change?

eilen is an adverb of time (“yesterday”). Finnish word order is quite flexible, so you can put eilen at the beginning (Eilen siirsin…), middle, or end without changing the basic meaning.

Is there an explicit word for “I” in this sentence?

No. Finnish often drops the subject pronoun when the verb ending already indicates the subject. Here -n on siirsin tells you the subject is “I.”

How is the past tense formed for siirtää, and what verb type is it?

siirtää is a Type I verb (infinitive ends in -taa). To form the past, you add -si- to the stem siirt-, giving siirsi-, and then add the personal ending -n to get siirsin.