scrub csrub srcub rscub crsub rcsub scurb csurb sucrb uscrb cusrb ucsrb srucb rsucb surcb usrcb ruscb urscb crusb rcusb cursb ucrsb rucsb urcsb scrbu csrbu srcbu rscbu crsbu rcsbu scbru csbru sbcru bscru cbsru bcsru srbcu rsbcu sbrcu bsrcu rbscu brscu crbsu rcbsu cbrsu bcrsu rbcsu brcsu scubr csubr sucbr uscbr cusbr ucsbr scbur csbur sbcur bscur cbsur bcsur subcr usbcr sbucr bsucr ubscr buscr cubsr ucbsr cbusr bcusr ubcsr bucsr srubc rsubc surbc usrbc rusbc ursbc srbuc rsbuc sbruc bsruc rbsuc brsuc subrc usbrc sburc bsurc ubsrc busrc rubsc urbsc rbusc brusc ubrsc bursc crubs rcubs curbs ucrbs rucbs urcbs crbus rcbus cbrus bcrus rbcus brcus cubrs ucbrs cburs bcurs ubcrs bucrs rubcs urbcs rbucs brucs ubrcs burcs
Note: these 'words' (valid or invalid) are all the permutations of the word scrub. These words are obtained by scrambling the letters in scrub.