frugs rfugs furgs ufrgs rufgs urfgs frgus rfgus fgrus gfrus rgfus grfus fugrs ufgrs fgurs gfurs ugfrs gufrs rugfs urgfs rgufs grufs ugrfs gurfs frusg rfusg fursg ufrsg rufsg urfsg frsug rfsug fsrug sfrug rsfug srfug fusrg ufsrg fsurg sfurg usfrg sufrg rusfg ursfg rsufg srufg usrfg surfg frgsu rfgsu fgrsu gfrsu rgfsu grfsu frsgu rfsgu fsrgu sfrgu rsfgu srfgu fgsru gfsru fsgru sfgru gsfru sgfru rgsfu grsfu rsgfu srgfu gsrfu sgrfu fugsr ufgsr fgusr gfusr ugfsr gufsr fusgr ufsgr fsugr sfugr usfgr sufgr fgsur gfsur fsgur sfgur gsfur sgfur ugsfr gusfr usgfr sugfr gsufr sgufr rugsf urgsf rgusf grusf ugrsf gursf rusgf ursgf rsugf srugf usrgf surgf rgsuf grsuf rsguf srguf gsruf sgruf ugsrf gusrf usgrf sugrf gsurf sgurf
Note: these 'words' (valid or invalid) are all the permutations of the word frugs. These words are obtained by scrambling the letters in frugs.