rowts orwts rwots wrots owrts worts rotws ortws rtows trows otrws torws rwtos wrtos rtwos trwos wtros twros owtrs wotrs otwrs towrs wtors twors rowst orwst rwost wrost owrst worst roswt orswt rsowt srowt osrwt sorwt rwsot wrsot rswot srwot wsrot swrot owsrt wosrt oswrt sowrt wsort swort rotsw ortsw rtosw trosw otrsw torsw rostw orstw rsotw srotw osrtw sortw rtsow trsow rstow srtow tsrow strow otsrw tosrw ostrw sotrw tsorw storw rwtso wrtso rtwso trwso wtrso twrso rwsto wrsto rswto srwto wsrto swrto rtswo trswo rstwo srtwo tsrwo strwo wtsro twsro wstro swtro tswro stwro owtsr wotsr otwsr towsr wtosr twosr owstr wostr oswtr sowtr wsotr swotr otswr toswr ostwr sotwr tsowr stowr wtsor twsor wstor swtor tswor stwor
Note: these 'words' (valid or invalid) are all the permutations of the word rowts. These words are obtained by scrambling the letters in rowts.