turfs utrfs trufs rtufs urtfs rutfs tufrs utfrs tfurs fturs uftrs futrs trfus rtfus tfrus ftrus rftus frtus urfts rufts ufrts furts rfuts fruts tursf utrsf trusf rtusf urtsf rutsf tusrf utsrf tsurf sturf ustrf sutrf trsuf rtsuf tsruf struf rstuf srtuf urstf rustf usrtf surtf rsutf srutf tufsr utfsr tfusr ftusr uftsr futsr tusfr utsfr tsufr stufr ustfr sutfr tfsur ftsur tsfur stfur fstur sftur ufstr fustr usftr suftr fsutr sfutr trfsu rtfsu tfrsu ftrsu rftsu frtsu trsfu rtsfu tsrfu strfu rstfu srtfu tfsru ftsru tsfru stfru fstru sftru rfstu frstu rsftu srftu fsrtu sfrtu urfst rufst ufrst furst rfust frust ursft rusft usrft surft rsuft sruft ufsrt fusrt usfrt sufrt fsurt sfurt rfsut frsut rsfut srfut fsrut sfrut
Note: these 'words' (valid or invalid) are all the permutations of the word turfs. These words are obtained by scrambling the letters in turfs.