thirl htirl tihrl ithrl hitrl ihtrl thril htril trhil rthil hrtil rhtil tirhl itrhl trihl rtihl irthl rithl hirtl ihrtl hritl rhitl irhtl rihtl thilr htilr tihlr ithlr hitlr ihtlr thlir htlir tlhir lthir hltir lhtir tilhr itlhr tlihr ltihr ilthr lithr hiltr ihltr hlitr lhitr ilhtr lihtr thrli htrli trhli rthli hrtli rhtli thlri htlri tlhri lthri hltri lhtri trlhi rtlhi tlrhi ltrhi rlthi lrthi hrlti rhlti hlrti lhrti rlhti lrhti tirlh itrlh trilh rtilh irtlh ritlh tilrh itlrh tlirh ltirh iltrh litrh trlih rtlih tlrih ltrih rltih lrtih irlth rilth ilrth lirth rlith lrith hirlt ihrlt hrilt rhilt irhlt rihlt hilrt ihlrt hlirt lhirt ilhrt lihrt hrlit rhlit hlrit lhrit rlhit lrhit irlht rilht ilrht lirht rliht lriht
Note: these 'words' (valid or invalid) are all the permutations of the word thirl. These words are obtained by scrambling the letters in thirl.