Questions & Answers about Onko tämä kuparia?
Why is kuparia in the partitive case instead of the nominative?
In this sentence, kuparia acts as the subject complement (describing the subject tämä). Because copper is a mass noun—an uncountable material or substance—Finnish requires it to be in the partitive case here rather than the basic nominative case.
Could I say Onko tämä kupari? using the nominative case?
Not when asking about the material. Using the nominative kupari would mean "Is this the (specific) copper?" as if it were a countable, whole object. For materials and substances like wood, water, or metal, you need the partitive to mean that the item consists of that substance.
If kuparia is partitive, why isn't the subject tämä also partitive?
The word tämä (this) refers to a specific, concrete object you are likely pointing at or holding, so it acts as a normal subject in the nominative case. In "A is B" sentences, the subject and the complement do not have to match cases. Only the complement (kuparia) changes to partitive to show what kind of material the subject is.
The lesson mentions this rule also applies to abstract subjects. How is that similar to this sentence?
Just like mass nouns (physical materials like kuparia or vettä), abstract concepts are also treated as uncountable. Therefore, they follow the exact same rule. Just as you say Tämä on kuparia (This is copper), you would use the partitive to say Tämä on rakkautta (This is love) or Tämä on totta (This is true).
Learn Onko tämä kuparia and more in Finnish
All course content and exercises are completely free — no paywalls, no trial periods, no signup needed.
- ✓ Practice with interactive exercises
- ✓ Track your progress with spaced repetition
- ✓Learn at your own pace — completely free