x1 is a part of Lojban text representing rule 'text' according to the first edition of the book 'The Complete Lojban Language'.
Inner structure of the rule: (NAI+)? (CMENE+ # | (indicators & free+))? (joik-jek)? text-1. Names in lower case are grammatical constructs. Names in UPPER CASE are selma'o (lexeme) names, and are terminals. Concatenation is expressed by juxtaposition with no operator symbol. '|' represents alternation (choice). '?' represents an optional element. '&' represents 'and/or' ('A & B' is the same as 'A | B | A B'). '+' represents optional repetition of the construct to the left. Left-grouping is implied; right-grouping is shown by explicit self-referential recursion with no '+'. '*' represents optional repetition of the construct to the left starting from 0 occurrences. Left-grouping is implied; right-grouping is shown by explicit self-referential recursion with no '*'. '()' serves to indicate the grouping of the other operators. Otherwise, '+' binds closer than '&', which binds closer than '|'. '#' is shorthand for '[free+]', a construct which appears in many places. '//' encloses an elidable terminator, which may be omitted (without change of meaning) if no grammatical ambiguity results.