rel ca'u lujvo

x₁ is the area (2-dimensional space) occupied by x₂

See re, canlu, cimde, cibyca'u, te'ai

jbovlaste

In notes:

cibyca'u: x₁ is the volume (3-dimensional space) occupied by x₂
rokrelca'u: x1 is a terrain characterized by rock x2