x_{1} is recursively related to x_{2} by applying x_{3} (number) levels-of-recursion of the predicate-relation x_{4} (ka with two ce'u)

Shortening of refkusi for more convenience in making V'y-style zi'evla-lujvo. tanru example for common usage: 'the day three days from now (tomorrow's tomorrow's tomorrow)' is 'lo bavlamdei efku be fi li ci'. Cf. krefu, rapli, efku

- cimny'efku
- x
_{1}is infinitely recursively related to x_{2}by applying infinite levels of recursion to predicate relation x_{3}(ka with two ce'u) - xaby'efku
- x
_{1}=xadba_{1}=efku_{1}is an exact/approximate half of a half of a half... of x_{2}=xadba_{2}=efku_{2}, cut in half exactly x_{3}=efku_{3}times, by standard x_{4}=xadba_{3} - faubganke
- x
_{1}happens, then if x_{2}is true, x_{1}repeatedly happens as long as x_{2}is true - ganfauke
- if x
_{1}is true, x_{2}happens, then repeats as long as x_{1}is true - iinsi
- x
_{1}(sequence) is a chain, the neighbouring elements of which are related by x_{2}(ckini_{3}, former element in sequence first) - refkusi
- x
_{1}is recursively related to x_{2}by applying x_{3}(number) levels-of-recursion of the predicate-relation x_{4}(ka with two ce'u) - utka
- x
_{1}and x_{2}are path-linked by binary predicate x_{3}(ka) via intermediate steps x_{4}(ce'o; (ordered) list).