crura rcura curra ucrra rucra urcra crrua rcrua crrua rcrua rrcua rrcua curra ucrra crura rcura urcra rucra rurca urrca rruca rruca urrca rurca cruar rcuar curar ucrar rucar urcar craur rcaur carur acrur racur arcur cuarr ucarr caurr acurr uacrr aucrr ruacr uracr raucr arucr uarcr aurcr crrau rcrau crrau rcrau rrcau rrcau craru rcaru carru acrru racru arcru craru rcaru carru acrru racru arcru rracu rracu rarcu arrcu rarcu arrcu curar ucrar cruar rcuar urcar rucar cuarr ucarr caurr acurr uacrr aucrr craur rcaur carur acrur racur arcur uracr ruacr uarcr aurcr raucr arucr rurac urrac rruac rruac urrac rurac ruarc urarc raurc arurc uarrc aurrc rrauc rrauc raruc arruc raruc arruc urarc ruarc uarrc aurrc raurc arurc
Note: these 'words' (valid or invalid) are all the permutations of the word crura. These words are obtained by scrambling the letters in crura.