mtesr tmesr metsr emtsr temsr etmsr mtser tmser mster smter tsmer stmer mestr emstr msetr smetr esmtr semtr tesmr etsmr tsemr stemr estmr setmr mters tmers metrs emtrs temrs etmrs mtres tmres mrtes rmtes trmes rtmes merts emrts mrets rmets ermts remts terms etrms trems rtems ertms retms mtsre tmsre mstre smtre tsmre stmre mtrse tmrse mrtse rmtse trmse rtmse msrte smrte mrste rmste srmte rsmte tsrme strme trsme rtsme srtme rstme mesrt emsrt msert smert esmrt semrt merst emrst mrest rmest ermst remst msret smret mrset rmset srmet rsmet esrmt sermt ersmt resmt sremt rsemt tesrm etsrm tserm sterm estrm setrm tersm etrsm tresm rtesm ertsm retsm tsrem strem trsem rtsem srtem rstem esrtm sertm erstm restm sretm rsetm
Note: these 'words' (valid or invalid) are all the permutations of the word mtesr. These words are obtained by scrambling the letters in mtesr.