fasti afsti fsati sfati asfti safti fatsi aftsi ftasi tfasi atfsi tafsi fstai sftai ftsai tfsai stfai tsfai astfi satfi atsfi tasfi stafi tsafi fasit afsit fsait sfait asfit safit faist afist fiast ifast aifst iafst fsiat sfiat fisat ifsat sifat isfat asift saift aisft iasft siaft isaft fatis aftis ftais tfais atfis tafis faits afits fiats ifats aifts iafts ftias tfias fitas iftas tifas itfas atifs taifs aitfs iatfs tiafs itafs fstia sftia ftsia tfsia stfia tsfia fsita sfita fista ifsta sifta isfta ftisa tfisa fitsa iftsa tifsa itfsa stifa tsifa sitfa istfa tisfa itsfa astif satif atsif tasif staif tsaif asitf saitf aistf iastf siatf isatf atisf taisf aitsf iatsf tiasf itasf stiaf tsiaf sitaf istaf tisaf itsaf
Note: these 'words' (valid or invalid) are all the permutations of the word fasti. These words are obtained by scrambling the letters in fasti.