nebca enbca nbeca bneca ebnca benca necba encba nceba cneba ecnba cenba nbcea bncea ncbea cnbea bcnea cbnea ebcna becna ecbna cebna bcena cbena nebac enbac nbeac bneac ebnac benac neabc enabc naebc anebc eanbc aenbc nbaec bnaec nabec anbec banec abnec ebanc beanc eabnc aebnc baenc abenc necab encab nceab cneab ecnab cenab neacb enacb naecb anecb eancb aencb ncaeb cnaeb naceb anceb caneb acneb ecanb ceanb eacnb aecnb caenb acenb nbcae bncae ncbae cnbae bcnae cbnae nbace bnace nabce anbce bance abnce ncabe cnabe nacbe ancbe canbe acnbe bcane cbane bacne abcne cabne acbne ebcan becan ecban ceban bcean cbean ebacn beacn eabcn aebcn baecn abecn ecabn ceabn eacbn aecbn caebn acebn bcaen cbaen bacen abcen caben acben
Note: these 'words' (valid or invalid) are all the permutations of the word nebca. These words are obtained by scrambling the letters in nebca.