shrue hsrue srhue rshue hrsue rhsue shure hsure suhre ushre husre uhsre sruhe rsuhe surhe usrhe rushe urshe hruse rhuse hurse uhrse ruhse urhse shreu hsreu srheu rsheu hrseu rhseu sheru hseru sehru eshru hesru ehsru srehu rsehu serhu esrhu reshu ershu hresu rhesu hersu ehrsu rehsu erhsu shuer hsuer suher usher huser uhser sheur hseur sehur eshur hesur ehsur suehr usehr seuhr esuhr ueshr eushr huesr uhesr heusr ehusr uehsr euhsr srueh rsueh sureh usreh ruseh urseh sreuh rseuh seruh esruh resuh ersuh suerh userh seurh esurh uesrh eusrh ruesh uresh reush erush uersh eursh hrues rhues hures uhres ruhes urhes hreus rheus herus ehrus rehus erhus huers uhers heurs ehurs uehrs euhrs ruehs urehs reuhs eruhs uerhs eurhs
Note: these 'words' (valid or invalid) are all the permutations of the word shrue. These words are obtained by scrambling the letters in shrue.