furca ufrca fruca rfuca urfca rufca fucra ufcra fcura cfura ucfra cufra frcua rfcua fcrua cfrua rcfua crfua urcfa rucfa ucrfa curfa rcufa crufa furac ufrac fruac rfuac urfac rufac fuarc ufarc faurc afurc uafrc aufrc frauc rfauc faruc afruc rafuc arfuc urafc ruafc uarfc aurfc raufc arufc fucar ufcar fcuar cfuar ucfar cufar fuacr ufacr faucr afucr uafcr aufcr fcaur cfaur facur afcur cafur acfur ucafr cuafr uacfr aucfr caufr acufr frcau rfcau fcrau cfrau rcfau crfau fracu rfacu farcu afrcu rafcu arfcu fcaru cfaru facru afcru cafru acfru rcafu crafu racfu arcfu carfu acrfu urcaf rucaf ucraf curaf rcuaf cruaf uracf ruacf uarcf aurcf raucf arucf ucarf cuarf uacrf aucrf caurf acurf rcauf crauf racuf arcuf caruf acruf
Note: these 'words' (valid or invalid) are all the permutations of the word furca. These words are obtained by scrambling the letters in furca.