ferms efrms frems rfems erfms refms femrs efmrs fmers mfers emfrs mefrs frmes rfmes fmres mfres rmfes mrfes ermfs remfs emrfs merfs rmefs mrefs fersm efrsm fresm rfesm erfsm refsm fesrm efsrm fserm sferm esfrm sefrm frsem rfsem fsrem sfrem rsfem srfem ersfm resfm esrfm serfm rsefm srefm femsr efmsr fmesr mfesr emfsr mefsr fesmr efsmr fsemr sfemr esfmr sefmr fmser mfser fsmer sfmer msfer smfer emsfr mesfr esmfr semfr msefr smefr frmse rfmse fmrse mfrse rmfse mrfse frsme rfsme fsrme sfrme rsfme srfme fmsre mfsre fsmre sfmre msfre smfre rmsfe mrsfe rsmfe srmfe msrfe smrfe ermsf remsf emrsf mersf rmesf mresf ersmf resmf esrmf sermf rsemf sremf emsrf mesrf esmrf semrf mserf smerf rmsef mrsef rsmef srmef msref smref
Note: these 'words' (valid or invalid) are all the permutations of the word ferms. These words are obtained by scrambling the letters in ferms.