setmice fu'ivla

x₁ is a set (mathematical) consisting of elements x₂, x₃, x₄, etc.

See setmima, ce, porsice, gunmace, menrece

jbovlaste

In notes:

fi'ai (exp!): marks end of prenex in stack-based dialect
gunmace: x₁ is a mass/group consisting of elements x₂, x₃, x₄, etc.
menrece: x₁ is among x₂, x₃, x₄, etc.
porsice: x₁ is an ordered sequence consisting of elements x₂, x₃, x₄, etc.