c-cd cccc cccu ccdc ccdr ccoc ccod ccrc ccuc cd-r cddr ckck ckco ckdo ckdu ckoc ckoo ckor ckrc ckrd cock coco cocu codd cok- coko cood cook cor- corc cord cork coro corr coud couk cour crcc crcr crdc crkc croc crod crok croo cror crud cruk cucc cuck cuk- curd curo curr dccc dccu dcrk dddd ddoc ddrc dkdc dock doco docu dod- dodd dodo doko dood dook door dorc dord dork doro dorr doru douc doud douk dour drod drou druk druu duck duco dudd dudo dudu duku duo- durk duro duru duur kccc kccd kcck kccr kccu kcdc kcdd kcdr kcdu kckc kckk kcko kckr kcor kcou kcrc kcro kcrr kcru kcuk kdcc kdcd kdco kdcr kddc kddd kddk kddr kdkd kdkk kdko kdkr kdoc kdok kdro kduc kdur kkcd kkck kkco kkcr kkdc kkdd kkdo kkkk kkoo kkor kkrc kkrk kkro kkrr kkuu kocd kock kodk kodo kodu kokc kokk koko kokr koku kooc kook kooo koor koou korc kord kork koro korr koru kour kouu krcc krcd krco krcu krdc krdd krdo krdr krdu krkc krkd krkk krko krkr krku kroc krod krok kroo kror krrc krrk krro krrr kruc kruk krur kucc kucd kuco kucr kudd kudo kudu kukk kuku kuok kuoo kurd kurk kuro kurr kuru kuuk kuur kuuu occc ocro ocrr ocur oddd odoo odor odou odur okcu okko okok okor okro okur oocr ooku oooo oord orco ordo ordu orko oro- orok oror orro oucc oudc our- ouro ouu- rccc rcdc rcrd rdoc rocc rock roco rodd rodo rokk roko rokr roku rood rook roor rorc rork roro roru roud rouk rrrr ruck rudd rudo rukk ruku ruok rurc rurd ruro ruru ruud ucdc ucdd ucrc udoo uduk ukcc ukko ukok ukrc ukur uocc uor- urdu uro- urok uroo uruk urur uuoc uuuu