aaaa aaab aaar aaba aabb aaoo aara aaro aaru abaa abab abar abau abax abb- abba abbb abbo abbr aboa abob aboo abor abou abox abra abro abua aoba aora aorb arab arar arau arax arba aroa arob aroo aror arr- arra arro arrr arru arua arub auaa aur- aura auro auxa axar axo- axoa axxo ba-x baaa baar baba babb babo babr babu bar- bara barb baro barr baru barx bau- baur baux bbau bbbb bbox boab boar boba bobb bobo bobu boob boor boox bor- bora boro borr boru boua bour boxa brab brao brau brax broa brob broo bror brou brox brrr brux buar buba bubb bubo bubu bur- bura burb buro burr buru buxa oaau oara obba obbo obor obox obra obro ooaa ooba oooo oora orab orao orar orba orbb orbo orbu oro- oror orra orro orub our- oura ouro ouu- oxa- oxo- oxox oxxo raab raba rabb rabo rabu raob rara rarb raro raua raub raxa rbbb rbbr roab roar rob- roba robb robo robu roob roor roox rora roro roru roua roub roux roxa roxo rrrr ruba rubb rubu rura ruro ruru uaru uaua ubar ubba ubbo ubra uor- urao urau urba uro- uroa uroo urox urra urur uuuu uxor xaar xara xbar xbox xbra xoro xoxo xura xuxa xuxu xxxo xxxx