poufs opufs puofs upofs oupfs uopfs pofus opfus pfous fpous ofpus fopus pufos upfos pfuos fpuos ufpos fupos oufps uofps ofups foups ufops fuops pousf opusf puosf uposf oupsf uopsf posuf opsuf psouf spouf ospuf sopuf pusof upsof psuof spuof uspof supof ouspf uospf osupf soupf usopf suopf pofsu opfsu pfosu fposu ofpsu fopsu posfu opsfu psofu spofu ospfu sopfu pfsou fpsou psfou spfou fspou sfpou ofspu fospu osfpu sofpu fsopu sfopu pufso upfso pfuso fpuso ufpso fupso pusfo upsfo psufo spufo uspfo supfo pfsuo fpsuo psfuo spfuo fspuo sfpuo ufspo fuspo usfpo sufpo fsupo sfupo oufsp uofsp ofusp fousp ufosp fuosp ousfp uosfp osufp soufp usofp suofp ofsup fosup osfup sofup fsoup sfoup ufsop fusop usfop sufop fsuop sfuop
Note: these 'words' (valid or invalid) are all the permutations of the word poufs. These words are obtained by scrambling the letters in poufs.