preops rpeops perops eprops repops erpops proeps rpoeps poreps opreps ropeps orpeps peorps eporps poerps operps eoprps oeprps reopps eropps roepps orepps eorpps oerpps prepos rpepos perpos eprpos reppos erppos prpeos rppeos ppreos ppreos rppeos prpeos pepros eppros pperos pperos eppros pepros reppos erppos rpepos prepos eprpos perpos propes rpopes porpes oprpes roppes orppes prpoes rppoes pproes pproes rppoes prpoes popres oppres ppores ppores oppres popres roppes orppes rpopes propes oprpes porpes peoprs epoprs poeprs opeprs eopprs oepprs pepors eppors ppeors ppeors eppors pepors popers oppers ppoers ppoers oppers popers eopprs oepprs epoprs peoprs opeprs poeprs reopps eropps roepps orepps eorpps oerpps repops erpops rpeops preops eprops perops ropeps orpeps rpoeps proeps opreps poreps eoprps oeprps eporps peorps operps poerps preosp rpeosp perosp eprosp reposp erposp proesp rpoesp poresp opresp ropesp orpesp peorsp eporsp poersp opersp eoprsp oeprsp reopsp eropsp roepsp orepsp eorpsp oerpsp presop rpesop persop eprsop repsop erpsop prseop rpseop psreop spreop rspeop srpeop pesrop epsrop pserop sperop esprop seprop respop erspop rsepop srepop esrpop serpop prosep rposep porsep oprsep ropsep orpsep prsoep rpsoep psroep sproep rspoep srpoep posrep opsrep psorep sporep osprep soprep rospep orspep rsopep sropep osrpep sorpep peosrp eposrp poesrp opesrp eopsrp oepsrp pesorp epsorp pseorp speorp esporp seporp poserp opserp psoerp spoerp osperp soperp eosprp oesprp esoprp seoprp oseprp soeprp reospp erospp roespp orespp eorspp oerspp resopp ersopp rseopp sreopp esropp seropp rosepp orsepp rsoepp sroepp osrepp sorepp eosrpp oesrpp esorpp seorpp oserpp soerpp prepso rpepso perpso eprpso reppso erppso prpeso rppeso ppreso ppreso rppeso prpeso peprso epprso pperso pperso epprso peprso reppso erppso rpepso prepso eprpso perpso prespo rpespo perspo eprspo repspo erpspo prsepo rpsepo psrepo sprepo rspepo srpepo pesrpo epsrpo pserpo sperpo esprpo seprpo resppo ersppo rseppo sreppo esrppo serppo prpseo rppseo pprseo pprseo rppseo prpseo prspeo rpspeo psrpeo sprpeo rsppeo srppeo ppsreo ppsreo pspreo sppreo pspreo sppreo rpspeo prspeo rsppeo srppeo psrpeo sprpeo pepsro eppsro ppesro ppesro eppsro pepsro pespro epspro psepro spepro esppro seppro ppsero ppsero pspero sppero pspero sppero epspro pespro esppro seppro psepro spepro repspo erpspo rpespo prespo eprspo perspo resppo ersppo rseppo sreppo esrppo serppo rpsepo prsepo rspepo srpepo psrepo sprepo epsrpo pesrpo esprpo seprpo pserpo sperpo propse rpopse porpse oprpse roppse orppse prpose rppose pprose pprose rppose prpose poprse opprse pporse pporse opprse poprse roppse orppse rpopse propse oprpse porpse prospe rpospe porspe oprspe ropspe orpspe prsope rpsope psrope sprope rspope srpope posrpe opsrpe psorpe sporpe osprpe soprpe rosppe orsppe rsoppe sroppe osrppe sorppe prpsoe rppsoe pprsoe pprsoe rppsoe prpsoe prspoe rpspoe psrpoe sprpoe rsppoe srppoe ppsroe ppsroe psproe spproe psproe spproe rpspoe prspoe rsppoe srppoe psrpoe sprpoe popsre oppsre pposre pposre oppsre popsre pospre opspre psopre spopre osppre soppre ppsore ppsore pspore sppore pspore sppore opspre pospre osppre soppre psopre spopre ropspe orpspe rpospe prospe oprspe porspe rosppe orsppe rsoppe sroppe osrppe sorppe rpsope prsope rspope srpope psrope sprope opsrpe posrpe osprpe soprpe psorpe sporpe peopsr epopsr poepsr opepsr eoppsr oeppsr peposr epposr ppeosr ppeosr epposr peposr popesr oppesr ppoesr ppoesr oppesr popesr eoppsr oeppsr epopsr peopsr opepsr poepsr peospr epospr poespr opespr eopspr oepspr pesopr epsopr pseopr speopr espopr sepopr posepr opsepr psoepr spoepr ospepr sopepr eosppr oesppr esoppr seoppr oseppr soeppr pepsor eppsor ppesor ppesor eppsor pepsor pespor epspor psepor spepor esppor seppor ppseor ppseor pspeor sppeor pspeor sppeor epspor pespor esppor seppor psepor spepor popser oppser pposer pposer oppser popser posper opsper psoper spoper ospper sopper ppsoer ppsoer pspoer sppoer pspoer sppoer opsper posper ospper sopper psoper spoper eopspr oepspr epospr peospr opespr poespr eosppr oesppr esoppr seoppr oseppr soeppr epsopr pesopr espopr sepopr pseopr speopr opsepr posepr ospepr sopepr psoepr spoepr reopsp eropsp roepsp orepsp eorpsp oerpsp reposp erposp rpeosp preosp eprosp perosp ropesp orpesp rpoesp proesp opresp poresp eoprsp oeprsp eporsp peorsp opersp poersp reospp erospp roespp orespp eorspp oerspp resopp ersopp rseopp sreopp esropp seropp rosepp orsepp rsoepp sroepp osrepp sorepp eosrpp oesrpp esorpp seorpp oserpp soerpp repsop erpsop rpesop presop eprsop persop respop erspop rsepop srepop esrpop serpop rpseop prseop rspeop srpeop psreop spreop epsrop pesrop esprop seprop pserop sperop ropsep orpsep rposep prosep oprsep porsep rospep orspep rsopep sropep osrpep sorpep rpsoep prsoep rspoep srpoep psroep sproep opsrep posrep osprep soprep psorep sporep eopsrp oepsrp eposrp peosrp opesrp poesrp eosprp oesprp esoprp seoprp oseprp soeprp epsorp pesorp esporp seporp pseorp speorp opserp poserp osperp soperp psoerp spoerp
Note: these 'words' (valid or invalid) are all the permutations of the word preops. These words are obtained by scrambling the letters in preops.