forbs ofrbs frobs rfobs orfbs rofbs fobrs ofbrs fbors bfors obfrs bofrs frbos rfbos fbros bfros rbfos brfos orbfs robfs obrfs borfs rbofs brofs forsb ofrsb frosb rfosb orfsb rofsb fosrb ofsrb fsorb sforb osfrb sofrb frsob rfsob fsrob sfrob rsfob srfob orsfb rosfb osrfb sorfb rsofb srofb fobsr ofbsr fbosr bfosr obfsr bofsr fosbr ofsbr fsobr sfobr osfbr sofbr fbsor bfsor fsbor sfbor bsfor sbfor obsfr bosfr osbfr sobfr bsofr sbofr frbso rfbso fbrso bfrso rbfso brfso frsbo rfsbo fsrbo sfrbo rsfbo srfbo fbsro bfsro fsbro sfbro bsfro sbfro rbsfo brsfo rsbfo srbfo bsrfo sbrfo orbsf robsf obrsf borsf rbosf brosf orsbf rosbf osrbf sorbf rsobf srobf obsrf bosrf osbrf sobrf bsorf sborf rbsof brsof rsbof srbof bsrof sbrof
Note: these 'words' (valid or invalid) are all the permutations of the word forbs. These words are obtained by scrambling the letters in forbs.