nerks enrks nreks rneks ernks renks nekrs enkrs nkers kners eknrs kenrs nrkes rnkes nkres knres rknes krnes erkns rekns ekrns kerns rkens krens nersk enrsk nresk rnesk ernsk rensk nesrk ensrk nserk snerk esnrk senrk nrsek rnsek nsrek snrek rsnek srnek ersnk resnk esrnk sernk rsenk srenk neksr enksr nkesr knesr eknsr kensr neskr enskr nsekr snekr esnkr senkr nkser knser nsker snker ksner skner eksnr kesnr esknr seknr ksenr skenr nrkse rnkse nkrse knrse rknse krnse nrske rnske nsrke snrke rsnke srnke nksre knsre nskre snkre ksnre sknre rksne krsne rskne srkne ksrne skrne erksn reksn ekrsn kersn rkesn kresn erskn reskn esrkn serkn rsekn srekn eksrn kesrn eskrn sekrn ksern skern rksen krsen rsken srken ksren skren
Note: these 'words' (valid or invalid) are all the permutations of the word nerks. These words are obtained by scrambling the letters in nerks.