a-do aaaa aaab aaad aaar aaba aabb aabd aada aaoo aara aard aaro abaa abab abad abar abax abb- abba abbb abbo abbr abda abdo aboa abob abod aboo abor abox abra abro adaa adab adad adao adar adba adda addd addo addr adob adod adoo ador adox adra adro aoba aora aorb arab arad arar arax arba arda ardo aroa arob arod aroo aror arr- arra arro arrr axar axo- axoa axxo ba-x baaa baad baar baba babb babo babr bada badb badd bado badr bar- bara barb bard baro barr barx bbad bbbb bbdd bbdo bbox bd-r boab boad boar boba bobb bobo boda bodb bodo boob bood boor boox bor- bora bord boro borr boxa brab brad brao brax brda brdo broa brob brod broo bror brox brrr d-bo daab daad daar daba dabb dabo dada dado dara darb dard daro darr dbar dddd do-x doab doar doba dobb dod- doda dodd dodo doob dood door dora dord doro dorr doxa draa drab drad drar drax drba drda drob drod drra dxab dxbr dxdr dxra dxrd dxrr dxrx dxxr dxxx oara obad obba obbo obor obox obra obro odax odbo odda oddd odoo odor odra ooaa ooba ooda oooo oora oord orab orad orao orar orba orbb orbo orda ordo oro- oror orra orro oxa- oxo- oxox oxxo raab raad raba rabb rabo rada radd rado radr radx raob rara rarb raro raxa rbbb rbbr roab road roar rob- roba robb robo roda rodd rodo roob rood roor roox rora roro roxa roxo rrad rrrr xaar xado xara xbar xbox xbra xoro xoxo xrdb xrod xxxo xxxx