sel pau lujvo

x₁ has part/consists of x₂

In notes:

pagbu: x₁ is a part/component/piece/portion/segment of x₂ [where x₂ is a whole/mass]; x₂ is partly x₁.
muvyselpau: x₁ has moving part x₂, which moves to destination x₃ from origin x₄ over path x₅
slepau: x₁=pagbu₁=selci₁ is an irreducible/fundamental/indivisible part or constituent or unit which partially composes whole x₂=pagbu₂.