ribas irbas rbias brias ibras biras riabs irabs raibs aribs iarbs airbs rbais brais rabis arbis baris abris ibars biars iabrs aibrs bairs abirs ribsa irbsa rbisa brisa ibrsa birsa risba irsba rsiba sriba isrba sirba rbsia brsia rsbia srbia bsria sbria ibsra bisra isbra sibra bsira sbira riasb irasb raisb arisb iarsb airsb risab irsab rsiab sriab israb sirab rasib arsib rsaib sraib asrib sarib iasrb aisrb isarb siarb asirb sairb rbasi brasi rabsi arbsi barsi abrsi rbsai brsai rsbai srbai bsrai sbrai rasbi arsbi rsabi srabi asrbi sarbi basri absri bsari sbari asbri sabri ibasr biasr iabsr aibsr baisr abisr ibsar bisar isbar sibar bsiar sbiar iasbr aisbr isabr siabr asibr saibr basir absir bsair sbair asbir sabir
Note: these 'words' (valid or invalid) are all the permutations of the word ribas. These words are obtained by scrambling the letters in ribas.