Word
Elinikä ei ole kaksinkertaistunut, mutta se on pitkä.
Meaning
The life expectancy has not doubled, but it is long.
Part of speech
sentence
Pronunciation
Course
Lesson
Breakdown of Elinikä ei ole kaksinkertaistunut, mutta se on pitkä.
olla
to be
se
it / he / she (of a person) / that
mutta
but
ei
no / not (negative verb)
Questions & Answers about Elinikä ei ole kaksinkertaistunut, mutta se on pitkä.
How do we break down the long word kaksinkertaistunut?
It is built in stages. It starts with the number kaksi (two). Adding the suffix -nkertainen creates the adjective kaksinkertainen (double/twofold). To turn this into a verb meaning "to become double", Finnish adds the suffix -stua, making kaksinkertaistua. Finally, it takes the NUT participle form (kaksinkertaistunut) because it is part of the negative perfect tense (ei ole ...).
Since this lesson is about fraction words like kolmannes (a third), does "a double" work the same way?
No, fractions and multipliers behave differently. Fractions use the suffix -nes to form nouns (like neljännes for a quarter). Multipliers instead use the adjective suffix -nkertainen (like kaksinkertainen). When describing proportions changing over time, Finnish strongly prefers turning these multipliers into verbs, as seen in this sentence with kaksinkertaistua.
Could I use kaksinkertaistanut instead of kaksinkertaistunut here?
No, because that changes the verb from intransitive to transitive. Kaksinkertaistunut comes from kaksinkertaistua (to double itself / to become double). If you used kaksinkertaistanut, it would be from kaksinkertaistaa (to double something), which would require an active subject deliberately doubling the life expectancy.