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