trecks rtecks tercks etrcks retcks ertcks trceks rtceks tcreks ctreks rcteks crteks tecrks etcrks tcerks cterks ectrks cetrks rectks erctks rcetks cretks ecrtks certks trekcs rtekcs terkcs etrkcs retkcs ertkcs trkecs rtkecs tkrecs ktrecs rktecs krtecs tekrcs etkrcs tkercs ktercs ektrcs ketrcs rektcs erktcs rketcs kretcs ekrtcs kertcs trckes rtckes tcrkes ctrkes rctkes crtkes trkces rtkces tkrces ktrces rktces krtces tckres ctkres tkcres ktcres cktres kctres rcktes crktes rkctes krctes ckrtes kcrtes teckrs etckrs tcekrs ctekrs ectkrs cetkrs tekcrs etkcrs tkecrs ktecrs ektcrs ketcrs tckers ctkers tkcers ktcers ckters kcters ecktrs cektrs ekctrs kectrs cketrs kcetrs reckts erckts rcekts crekts ecrkts cerkts rekcts erkcts rkects krects ekrcts kercts rckets crkets rkcets krcets ckrets kcrets eckrts cekrts ekcrts kecrts ckerts kcerts trecsk rtecsk tercsk etrcsk retcsk ertcsk trcesk rtcesk tcresk ctresk rctesk crtesk tecrsk etcrsk tcersk ctersk ectrsk cetrsk rectsk erctsk rcetsk cretsk ecrtsk certsk tresck rtesck tersck etrsck retsck ertsck trseck rtseck tsreck streck rsteck srteck tesrck etsrck tserck sterck estrck setrck restck erstck rsetck sretck esrtck sertck trcsek rtcsek tcrsek ctrsek rctsek crtsek trscek rtscek tsrcek strcek rstcek srtcek tcsrek ctsrek tscrek stcrek cstrek sctrek rcstek crstek rsctek srctek csrtek scrtek tecsrk etcsrk tcesrk ctesrk ectsrk cetsrk tescrk etscrk tsecrk stecrk estcrk setcrk tcserk ctserk tscerk stcerk csterk scterk ecstrk cestrk esctrk sectrk csetrk scetrk recstk ercstk rcestk crestk ecrstk cerstk resctk ersctk rsectk srectk esrctk serctk rcsetk crsetk rscetk srcetk csretk scretk ecsrtk cesrtk escrtk secrtk csertk scertk treksc rteksc terksc etrksc retksc ertksc trkesc rtkesc tkresc ktresc rktesc krtesc tekrsc etkrsc tkersc ktersc ektrsc ketrsc rektsc erktsc rketsc kretsc ekrtsc kertsc treskc rteskc terskc etrskc retskc ertskc trsekc rtsekc tsrekc strekc rstekc srtekc tesrkc etsrkc tserkc sterkc estrkc setrkc restkc erstkc rsetkc sretkc esrtkc sertkc trksec rtksec tkrsec ktrsec rktsec krtsec trskec rtskec tsrkec strkec rstkec srtkec tksrec ktsrec tskrec stkrec kstrec sktrec rkstec krstec rsktec srktec ksrtec skrtec teksrc etksrc tkesrc ktesrc ektsrc ketsrc teskrc etskrc tsekrc stekrc estkrc setkrc tkserc ktserc tskerc stkerc ksterc skterc ekstrc kestrc esktrc sektrc ksetrc sketrc rekstc erkstc rkestc krestc ekrstc kerstc resktc ersktc rsektc srektc esrktc serktc rksetc krsetc rsketc srketc ksretc skretc eksrtc kesrtc eskrtc sekrtc ksertc skertc trckse rtckse tcrkse ctrkse rctkse crtkse trkcse rtkcse tkrcse ktrcse rktcse krtcse tckrse ctkrse tkcrse ktcrse cktrse kctrse rcktse crktse rkctse krctse ckrtse kcrtse trcske rtcske tcrske ctrske rctske crtske trscke rtscke tsrcke strcke rstcke srtcke tcsrke ctsrke tscrke stcrke cstrke sctrke rcstke crstke rsctke srctke csrtke scrtke trksce rtksce tkrsce ktrsce rktsce krtsce trskce rtskce tsrkce strkce rstkce srtkce tksrce ktsrce tskrce stkrce kstrce sktrce rkstce krstce rsktce srktce ksrtce skrtce tcksre ctksre tkcsre ktcsre cktsre kctsre tcskre ctskre tsckre stckre cstkre sctkre tkscre ktscre tskcre stkcre kstcre sktcre ckstre kcstre csktre scktre ksctre skctre rckste crkste rkcste krcste ckrste kcrste rcskte crskte rsckte srckte csrkte scrkte rkscte krscte rskcte srkcte ksrcte skrcte cksrte kcsrte cskrte sckrte kscrte skcrte tecksr etcksr tceksr cteksr ectksr cetksr tekcsr etkcsr tkecsr ktecsr ektcsr ketcsr tckesr ctkesr tkcesr ktcesr cktesr kctesr ecktsr cektsr ekctsr kectsr cketsr kcetsr tecskr etcskr tceskr cteskr ectskr cetskr tesckr etsckr tseckr steckr estckr setckr tcsekr ctsekr tscekr stcekr cstekr sctekr ecstkr cestkr esctkr sectkr csetkr scetkr tekscr etkscr tkescr ktescr ektscr ketscr teskcr etskcr tsekcr stekcr estkcr setkcr tksecr ktsecr tskecr stkecr kstecr sktecr ekstcr kestcr esktcr sektcr ksetcr sketcr tckser ctkser tkcser ktcser cktser kctser tcsker ctsker tscker stcker cstker sctker tkscer ktscer tskcer stkcer kstcer sktcer ckster kcster cskter sckter kscter skcter eckstr cekstr ekcstr kecstr ckestr kcestr ecsktr cesktr escktr secktr csektr scektr eksctr kesctr eskctr sekctr ksectr skectr cksetr kcsetr csketr scketr kscetr skcetr reckst erckst rcekst crekst ecrkst cerkst rekcst erkcst rkecst krecst ekrcst kercst rckest crkest rkcest krcest ckrest kcrest eckrst cekrst ekcrst kecrst ckerst kcerst recskt ercskt rceskt creskt ecrskt cerskt resckt ersckt rseckt sreckt esrckt serckt rcsekt crsekt rscekt srcekt csrekt screkt ecsrkt cesrkt escrkt secrkt cserkt scerkt reksct erksct rkesct kresct ekrsct kersct reskct erskct rsekct srekct esrkct serkct rksect krsect rskect srkect ksrect skrect eksrct kesrct eskrct sekrct kserct skerct rckset crkset rkcset krcset ckrset kcrset rcsket crsket rscket srcket csrket scrket rkscet krscet rskcet srkcet ksrcet skrcet cksret kcsret cskret sckret kscret skcret ecksrt ceksrt ekcsrt kecsrt ckesrt kcesrt ecskrt ceskrt esckrt seckrt csekrt scekrt ekscrt kescrt eskcrt sekcrt ksecrt skecrt cksert kcsert cskert sckert kscert skcert
Note: these 'words' (valid or invalid) are all the permutations of the word trecks. These words are obtained by scrambling the letters in trecks.