ctbra tcbra cbtra bctra tbcra btcra ctrba tcrba crtba rctba trcba rtcba cbrta bcrta crbta rcbta brcta rbcta tbrca btrca trbca rtbca brtca rbtca ctbar tcbar cbtar bctar tbcar btcar ctabr tcabr catbr actbr tacbr atcbr cbatr bcatr cabtr acbtr bactr abctr tbacr btacr tabcr atbcr batcr abtcr ctrab tcrab crtab rctab trcab rtcab ctarb tcarb catrb actrb tacrb atcrb cratb rcatb cartb acrtb ractb arctb tracb rtacb tarcb atrcb ratcb artcb cbrat bcrat crbat rcbat brcat rbcat cbart bcart cabrt acbrt bacrt abcrt crabt rcabt carbt acrbt racbt arcbt bract rbact barct abrct rabct arbct tbrac btrac trbac rtbac brtac rbtac tbarc btarc tabrc atbrc batrc abtrc trabc rtabc tarbc atrbc ratbc artbc bratc rbatc bartc abrtc rabtc arbtc
Note: these 'words' (valid or invalid) are all the permutations of the word ctbra. These words are obtained by scrambling the letters in ctbra.