Learn Hardcore Finnish: Ostin opaskirjan, jossa jokainen nähtävyys on kuvattu lyhyesti. - I bought a guidebook in which every sight is described briefly.

ostin = osti (past stem) + -n (1st person singular ending) → “I bought”
You can say Minä ostin opaskirjan, but minä is only added for emphasis (e.g. “I bought the guidebook (not someone else)”).

So Finnish normally just uses ostin without minä.

Why does opaskirja have an -n at the end: opaskirjan?

The -n on opaskirjan marks the object case (often called genitive/accusative in grammar books).

Basic form: opaskirja = “guidebook”
Object form: opaskirjan = “(the) guidebook” as a complete object of a finished action

You use this -n object form when:

the object is singular, and
the action is completed / total: you bought one whole guidebook.

Compare:

Ostin opaskirjan. – “I bought a/the whole guidebook.”
Ostin opaskirjaa. – “I was buying a guidebook / I bought some guidebook (partitive, incomplete or vague).”

Here, the action is clearly completed, so opaskirjan is used.

What exactly does jossa mean, and why isn’t it just joka?

Jossa is a case form of joka (“which / that / who”).

joka = relative pronoun “which / that / who” (basic form)
jossa = joka in inessive case (“in which”)

So:

opaskirja, jossa… = “a guidebook in which …”

The -ssa part is the same “in” ending you know from place words:

talossa = “in the house”
kirjassa = “in the book”
jossa = “in which”

We use jossa here because the attractions are described in the guidebook.

What is jossa referring to in this sentence?

Jossa refers back to opaskirja(n), the guidebook:

Ostin opaskirjan, jossa jokainen nähtävyys on kuvattu lyhyesti.
→ “I bought a guidebook in which every sight is described briefly.”

Grammatically:

jossa is singular and inessive (“in which”)
Its antecedent is opaskirjan (the guidebook)

So the whole relative clause jossa jokainen nähtävyys on kuvattu lyhyesti is giving extra information about that guidebook.

Why is it jokainen nähtävyys (singular) instead of a plural like jokaiset nähtävyydet?

With jokainen (“each / every”), Finnish uses a singular noun, not a plural:

jokainen nähtävyys = “every sight / each attraction” (literally “each sight”)
Plural here would be ungrammatical: ✗ jokaiset nähtävyydet

Compare:

jokainen ihminen – every person
jokainen kirja – every book
jokainen nähtävyys – every sight

If you want a true plural “all the sights,” you use kaikki + plural:

kaikki nähtävyydet on kuvattu lyhyesti
= “all the sights are described briefly.”

But jokainen nähtävyys focuses on each individual attraction.

What exactly does nähtävyys mean and how is it formed?

Nähtävyys means roughly “sight / tourist attraction / place worth seeing.”

It’s built from:

nähdä = “to see”
Stem nähtä-
- suffix -vyys

The suffix -vyys often makes abstract nouns like:

tärkeä → tärkeys (“important → importance”)
kaunis → kauneus (“beautiful → beauty”)

For nähtävyys, the idea is “something that is to-be-seen / worth seeing” → “sight / attraction.”

How does on kuvattu work grammatically? Is it a tense, a passive, or what?

On kuvattu is a passive perfect form of the verb kuvata (“to describe, depict”).

Breakdown:

kuvata – to describe / depict
kuvattu – passive past participle → “(that has been) described”
on kuvattu – “has been described / is described”

Features:

It’s passive: no specific subject is mentioned.
→ “they have described”, “someone has described” → “is/has been described”
It’s in a perfect tense: it describes a completed result that’s relevant now.

So:

jokainen nähtävyys on kuvattu lyhyesti
= “each sight has been described briefly”
(or more loosely: “each sight is described briefly”)

No agent is specified; the focus is on the result (the sights are in a described state).

Could the verb part be kuvataan instead of on kuvattu? What would change?

Yes, you could say:

…jossa jokainen nähtävyys kuvataan lyhyesti.

Kuvataan is present passive:

kuvataan = “is (being) described” / “they describe”

Difference in nuance:

on kuvattu – perfect passive:
→ the description is already done, emphasizing the result/state.
“Each sight has been described briefly (in this book).”
kuvataan – present passive:
→ more like a timeless fact or process, neutral present tense.
“Each sight is described briefly (in this book).”

Both are acceptable; on kuvattu fits well if you’re thinking of the book as a finished product.

Why is there a comma before jossa in Finnish, when English often wouldn’t use one?

In standard written Finnish, you almost always put a comma before a subordinate clause, including those beginning with joka, jossa, että, koska, kun, etc.

So:

Ostin opaskirjan, jossa jokainen nähtävyys on kuvattu lyhyesti.

Even if in English you might write:

“I bought a guidebook that describes every sight briefly.” (often without a comma)

Finnish punctuation rules are stricter here: the comma marks the start of the relative clause. It doesn’t necessarily mean “non‑restrictive” vs “restrictive” the same way it does in English; it’s more a structural rule.

Could this mean “I bought the guidebook” or only “a guidebook”? There’s no article in Finnish.

Finnish has no articles (“a/an/the”), so Ostin opaskirjan can mean either:

“I bought a guidebook”
“I bought the guidebook”

Which one is meant depends entirely on context:

If it’s the first mention: readers usually interpret it as “a guidebook.”
If both speaker and listener already know which guidebook is being discussed (e.g. “the famous guidebook we talked about”), it can be understood as “the guidebook.”

The Finnish form opaskirjan itself does not mark this difference.

Can I change the word order inside the relative clause, like jossa on kuvattu jokainen nähtävyys lyhyesti?

Yes, you can, and it’s still grammatical:

jossa jokainen nähtävyys on kuvattu lyhyesti
jossa on kuvattu jokainen nähtävyys lyhyesti

Both mean essentially the same thing. Subtle differences:

jokainen nähtävyys on kuvattu lyhyesti
→ starts with the subject “each sight”, neutral, slightly more common.
on kuvattu jokainen nähtävyys lyhyesti
→ starts with the verb; can sound a bit more formal or stylistic, focusing more on the action/result (“has been described”) and then adding what was described.

Finnish word order is relatively flexible; information structure (what’s new or emphasized) can be adjusted by moving elements around.

What is lyhyesti and how is it formed?

Lyhyesti is an adverb meaning “briefly / shortly.”

It’s formed from the adjective lyhyt (“short”) plus the adverbial suffix -sti:

lyhyt → lyhyesti (short → briefly)
(the t changes to s in the stem: lyhyt → lyhye-
- -sti)

This -sti ending is a common way to form adverbs from adjectives:

nopea → nopeasti (fast → quickly)
hiljainen → hiljaa / hiljaisesti (quiet → quietly)
selvä → selvästi (clear → clearly)

So lyhyesti answers “how is it described?” → “briefly.”

Is opaskirja one word or two? Can I say opas kirja?

In this meaning, it’s one compound word: opaskirja.

opas = guide (person or thing that guides)
kirja = book
opaskirja = “guidebook” (a book that guides)

Writing opas kirja as two words would sound like “a guide, a book” or “guide book” in a very loose, non-compound way, and would not be standard for the established word “guidebook.”

Finnish often combines nouns into compounds without spaces when they form a fixed concept:

matka
- opas → matkaopas (travel guide)
keittiö
- pöytä → keittiöpöytä (kitchen table)

So here, use the one-word form opaskirja.