bbbb bobb bobo bobu bomb bomt bomu boob boom boor boot bor- borm boro borr bort boru botb boto bott boum bour bout bovo brob brom broo bror brot brou brrm brrr brum brut bruv brvm btob btor btrt bttb bubb bubo bubu bum- bumb bur- burb burm buro burr burt buru but- buto butt mbou mmmm mmor mobb mobo momo momu moob moor moot moov morb moro mort moru motb motm moto mott motu mour mout movt mrbb mrbm mrtm mrtt mtbo mtom mtor mtrr mttr mtvr mtvu mubo mumm mumo mumu muro murr murt muru muto mutt mutu mutv muut mvtr obbo obor obot obro ombo ombu omo- omoo omor omov omro omuo oooo oort ootb orbb orbo orbu ormo oro- orom oror orot orro orto orub orum orvr oto- otoo otor otov otro otto ottu otur our- ouro ourt out- outb outo ouu- ovo- ovoo ovot ovum rbbb rbbr rmmv rmtu rmvb rob- robb robo robt robu romb romm romo roob room roor root roro rort roru roto rotr rott roub roum rout rovo rrrr rrum rubb rubu rumb rumm rumo rumt ruro ruru ruto rutt rutu ruvu t-mo tbrb tmbr tmou tmro tmtt tobo tobt tobu tomb tomm tomo tomt toom toor toot torm toro torr tort toru torv totm toto totr tott toum tour tout touv tovo trmb trmu trom troo trot trou trtr trub trut truu ttbb tttt tubb tubo tubr tubu tumb tumu tuor turb turm turo turr turt turu tuto tutt tutu tuum tuuo tvmt tvro tvrr tvtv ubbo umb- umbo ummo umor umtv umut uomo uor- uovo uro- urom uroo urum urur urut utmb utor utto uttu uuuu uv-b uvvu voom voor voot vor- vorm voro vort voru voto vour vout vrot vrto vurb vurt vutv vvob vvvv