nil nal ci'o lujvo

ni₁ is the age [elapsed duration] of c₁ by standard c₂

In notes:

citno: x₁ is young/youthful [relatively short in elapsed duration] by standard x₂.
bavyfarvi: f₁ ages / passes through time into future form f₂= b₁ from current / past / earlier form f₃= b₂ through stages f₄.
citmau: z₁=c₁ is younger than z₂ by amount z₄.
citrai: t₁=c₁ is youngest among t₄.
nilji'etei: ni₁ is the age of j₁ from time/event t₂ (default: birth) until reference time on scale ni3 (default: [{month}, year]).