Learn Hardcore Finnish: Jos skanneri on rikki, voi kopioida dokumentin ja lähettää sen kuvana. - If the scanner is broken, you can copy the document and send it as a photo.

Jos means if and introduces a conditional clause. In Finnish, the present tense is commonly used in if-clauses even when English might use “is” or “is going to be”:

Jos skanneri on rikki = If the scanner is broken.
No special “future” form is needed here.

What does on rikki literally mean, and why not an adjective like rikkinäinen?

on rikki is a very common fixed-style way to say something is broken/out of order. Literally it’s like “is broken” with rikki functioning as a predicative word after olla (to be).
rikkinäinen is also possible, but it can feel a bit more like describing the object as “broken (in condition)” rather than “not working.” In everyday language for devices, on rikki is extremely natural.

Why is there a comma after rikki?

Because the sentence begins with a subordinate clause (Jos...). Finnish typically uses a comma to separate the conditional clause from the main clause:

Jos X, Y. = If X, (then) Y.

Who is the subject of voi? It looks like “can,” but nobody is doing it.

There is no explicit subject. This is the Finnish zero person construction: voi + infinitive expresses a general “one can / you can / it’s possible to” meaning without specifying who.
So voi kopioida... is like you can copy... / one can copy... in a general instruction sense.

How would it change if I wanted to say “you can” to a specific person?

You would normally use voit (2nd person singular):

Jos skanneri on rikki, voit kopioida dokumentin ja lähettää sen kuvana.
That sounds like you’re speaking directly to one person.

Could this also be voidaan? What’s the difference from voi?

Yes, and the nuance changes:

voi kopioida = “one/you can copy” (general possibility; zero person)
voidaan kopioida = “it can be copied / we can copy” (passive; often implies people in general or “we” in an institutional sense)
Both can work in instructions; voi is very common for general advice.

Why are kopioida and lähettää in that form?

They are in the basic dictionary form, the 1st infinitive. Finnish modal verbs like voi are followed by the infinitive:

voi + kopioida = can copy
voi + lähettää = can send
Here the second verb (lähettää) is coordinated with the first: voi [kopioida …] ja [lähettää …].

Why is it dokumentin (ending -n) and not dokumenttia?

dokumentin is the total object form (often genitive-looking -n in the singular). It suggests the action is seen as complete: copy the whole document.
dokumenttia (partitive) would suggest an incomplete/ongoing or indefinite amount, like “copy some of the document” or “do some copying,” depending on context.

Why is it sen and not just se?

Because sen is the object form (accusative/genitive-like) of se (it). It refers back to dokumentin:

lähettää sen = send it
Using se would be the subject form and would sound wrong here.

What does kuvana mean grammatically? Why that ending?

kuvana is the essive case (-na/-nä), meaning “as a …” / “in the form of …”:

lähettää sen kuvana = send it as an image / send it in image form.
It describes the role/format in which the document is sent.

Could I also say kuvaksi instead of kuvana?

Sometimes, but it changes the feel:

kuvana (essive) = as an image (the sending happens in that form)
kuvaksi (translative) = into an image / to become an image (emphasizes a change of form)
For “send as an image,” kuvana is the straightforward choice.

Is the word order flexible? For example, can I move dokumentin earlier?

Finnish word order is fairly flexible, but changes emphasis. The given version is neutral. You could also say:

Jos skanneri on rikki, dokumentin voi kopioida ja lähettää sen kuvana.
That emphasizes dokumentin (the document) a bit more. The grammar remains fine.