spelt pselt seplt esplt peslt epslt splet pslet slpet lspet plset lpset selpt eslpt slept lsept elspt lespt pelst eplst plest lpest elpst lepst spetl psetl septl esptl pestl epstl sptel pstel stpel tspel ptsel tpsel setpl estpl stepl tsepl etspl tespl petsl eptsl ptesl tpesl etpsl tepsl splte pslte slpte lspte plste lpste sptle pstle stple tsple ptsle tpsle sltpe lstpe stlpe tslpe ltspe tlspe pltse lptse ptlse tplse ltpse tlpse seltp esltp sletp lsetp elstp lestp setlp estlp stelp tselp etslp teslp sltep lstep stlep tslep ltsep tlsep eltsp letsp etlsp telsp ltesp tlesp pelts eplts plets lpets elpts lepts petls eptls ptels tpels etpls tepls pltes lptes ptles tples ltpes tlpes eltps letps etlps telps lteps tleps
Note: these 'words' (valid or invalid) are all the permutations of the word spelt. These words are obtained by scrambling the letters in spelt.