proin rpoin porin oprin ropin orpin prion rpion piron ipron ripon irpon poirn opirn piorn iporn oiprn ioprn roipn oripn riopn iropn oirpn iorpn proni rponi porni oprni ropni orpni prnoi rpnoi pnroi nproi rnpoi nrpoi ponri opnri pnori npori onpri nopri ronpi ornpi rnopi nropi onrpi norpi prino rpino pirno iprno ripno irpno prnio rpnio pnrio nprio rnpio nrpio pinro ipnro pniro npiro inpro nipro rinpo irnpo rnipo nripo inrpo nirpo poinr opinr pionr iponr oipnr iopnr ponir opnir pnoir npoir onpir nopir pinor ipnor pnior npior inpor nipor oinpr ionpr onipr noipr inopr niopr roinp orinp rionp ironp oirnp iornp ronip ornip rnoip nroip onrip norip rinop irnop rniop nriop inrop nirop oinrp ionrp onirp noirp inorp niorp
Note: these 'words' (valid or invalid) are all the permutations of the word proin. These words are obtained by scrambling the letters in proin.