grund rgund gurnd ugrnd rugnd urgnd grnud rgnud gnrud ngrud rngud nrgud gunrd ugnrd gnurd ngurd ungrd nugrd rungd urngd rnugd nrugd unrgd nurgd grudn rgudn gurdn ugrdn rugdn urgdn grdun rgdun gdrun dgrun rdgun drgun gudrn ugdrn gdurn dgurn udgrn dugrn rudgn urdgn rdugn drugn udrgn durgn grndu rgndu gnrdu ngrdu rngdu nrgdu grdnu rgdnu gdrnu dgrnu rdgnu drgnu gndru ngdru gdnru dgnru ndgru dngru rndgu nrdgu rdngu drngu ndrgu dnrgu gundr ugndr gnudr ngudr ungdr nugdr gudnr ugdnr gdunr dgunr udgnr dugnr gndur ngdur gdnur dgnur ndgur dngur undgr nudgr udngr dungr ndugr dnugr rundg urndg rnudg nrudg unrdg nurdg rudng urdng rdung drung udrng durng rndug nrdug rdnug drnug ndrug dnrug undrg nudrg udnrg dunrg ndurg dnurg
Note: these 'words' (valid or invalid) are all the permutations of the word grund. These words are obtained by scrambling the letters in grund.