On grammatical class:

zi'e
joins relative clauses which apply to the same sumti.

In definition:

cmavrzi'e
x1 is the selma'o "ZIhE".

In notes:

loi zei binsasu
x1 is a part of Lojban text representing rule 'relative-clauses' according to the first edition of the book 'The Complete Lojban Language'.