frats rfats farts afrts rafts arfts frtas rftas ftras tfras rtfas trfas fatrs aftrs ftars tfars atfrs tafrs ratfs artfs rtafs trafs atrfs tarfs frast rfast farst afrst rafst arfst frsat rfsat fsrat sfrat rsfat srfat fasrt afsrt fsart sfart asfrt safrt rasft arsft rsaft sraft asrft sarft frtsa rftsa ftrsa tfrsa rtfsa trfsa frsta rfsta fsrta sfrta rsfta srfta ftsra tfsra fstra sftra tsfra stfra rtsfa trsfa rstfa srtfa tsrfa strfa fatsr aftsr ftasr tfasr atfsr tafsr fastr afstr fsatr sfatr asftr saftr ftsar tfsar fstar sftar tsfar stfar atsfr tasfr astfr satfr tsafr stafr ratsf artsf rtasf trasf atrsf tarsf rastf arstf rsatf sratf asrtf sartf rtsaf trsaf rstaf srtaf tsraf straf atsrf tasrf astrf satrf tsarf starf
Note: these 'words' (valid or invalid) are all the permutations of the word frats. These words are obtained by scrambling the letters in frats.