x1 (letteral: la'e zo BY/word-bu) is a hyphen/joining letter(al) in language x2 with function in/context of use/with rules for use/with properties x3, joining prefixed unit/lexeme/morpheme/string x4 (quote) to postfixed unit/lexeme/morpheme/string x5 (quote) in construct (full word) x6 (quote)
x1 joins words/morphemes/particles into a single cohesive, semantic or grammatical unit while also separating and distinguishing them into recognizable parts or functions. x4 and x5 may be improper quotes. In English, "-" is such a hyphen letteral; in Lojban, .ybu, ry, ny, and ly are such hyphen letterals (arguably, as is y'y). The fact that the letteral is used to join words/morphemes is implicit and this function therefore need not be specified in x3 in most cases.