preen rpeen peren epren repen erpen preen rpeen peren epren repen erpen peern epern peern epern eeprn eeprn reepn erepn reepn erepn eerpn eerpn prene rpene perne eprne repne erpne prnee rpnee pnree npree rnpee nrpee penre epnre pnere npere enpre nepre renpe ernpe rnepe nrepe enrpe nerpe prene rpene perne eprne repne erpne prnee rpnee pnree npree rnpee nrpee penre epnre pnere npere enpre nepre renpe ernpe rnepe nrepe enrpe nerpe peenr epenr peenr epenr eepnr eepnr pener epner pneer npeer enper neper pener epner pneer npeer enper neper eenpr eenpr enepr neepr enepr neepr reenp erenp reenp erenp eernp eernp renep ernep rneep nreep enrep nerep renep ernep rneep nreep enrep nerep eenrp eenrp enerp neerp enerp neerp
Note: these 'words' (valid or invalid) are all the permutations of the word preen. These words are obtained by scrambling the letters in preen.