plonk lponk polnk oplnk lopnk olpnk plnok lpnok pnlok nplok lnpok nlpok ponlk opnlk pnolk npolk onplk noplk lonpk olnpk lnopk nlopk onlpk nolpk plokn lpokn polkn oplkn lopkn olpkn plkon lpkon pklon kplon lkpon klpon pokln opkln pkoln kpoln okpln kopln lokpn olkpn lkopn klopn oklpn kolpn plnko lpnko pnlko nplko lnpko nlpko plkno lpkno pklno kplno lkpno klpno pnklo npklo pknlo kpnlo nkplo knplo lnkpo nlkpo lknpo klnpo nklpo knlpo ponkl opnkl pnokl npokl onpkl nopkl poknl opknl pkonl kponl okpnl kopnl pnkol npkol pknol kpnol nkpol knpol onkpl nokpl oknpl konpl nkopl knopl lonkp olnkp lnokp nlokp onlkp nolkp loknp olknp lkonp klonp oklnp kolnp lnkop nlkop lknop klnop nklop knlop onklp noklp oknlp konlp nkolp knolp
Note: these 'words' (valid or invalid) are all the permutations of the word plonk. These words are obtained by scrambling the letters in plonk.