bbbb bbin bibb bibi bibo biin bin- bini binn bino binu bio- bioi bion biou birb biri birn biro birr biru bnib bnin bnor bnrr bobb bobi bobo bobu boi- boii boin boiu boni bonn bono bonu boob boon boor bor- bori born boro borr boru boun bour brin brio brno brob bron broo bror brou brrr brun bubb bubi bubo bubu buin buir buiu bunb buni bunn buno bunu buon bur- burb buri burn buro burr buru i-no ibon ibri ibro iiii iiio iino iioi iioo inbo inni inno innr innu ino- inoi inon inor inou inri inro inui inun iobi ioii ioio ioni ionn iono iooi iooo iori ioun iri- irin irio irob iron irri irun iuiu iuno n-ii nbbo nibi nibo niir niiu nini nino nion nioo niou niro niru niur nnnn nobi nobo nobu noib noin noio noir non- noni nonn nono nonu noo- noob noon nooo noor nor- norb nori norn noro norr noun nour nron nubi nuin nunn nuno nuon nuri nurn nurr nuru obbo obin oboi obon obor obri obro oiii oion onir onni onno onon onor onur oobi oooo orbb orbi orbo orbu ori- orin orio orni orno oro- oron oror orri orro orub ouii ouin ouir oun- our- ourn ouro ouu- rbbb rbbr rib- ribo ribu riin rinn rino rion riou riri rnbr rnin rob- robb robi robo robu roin roio roir roiu roni rono roob rooi roon roor rori roro roru roub roun rrrr rrun rubb rubi rubu ruin runi runn runo ruri ruro ruru ruun ubbi ubbo ubii ubir ubon uirr uni- unii unin unio unir unni unno unon unro uor- urbi urib urin uriu urni uro- uroo urri urun urur uuni uuno uuri uuuu