-hou bbbb bbch bbrc bcbc bccc bcor bcru bcuc bhcc bhor bhur bhuu bobb bobo bobu boch boco bocu boho bohr bohu boob booc booh boor bor- borh boro borr boru bouh bour brcb brob broc broh broo bror brou brrr bruc bruh bubb bubo bubu bucc buch buco bucu buho buhr bur- burb burh buro burr buru c-bo cbbc cbcc cbcr cbcu cbrh ccbc cccb cccc cccu cchr ccob ccoc ccrc ccuc chch choc choh choo chor chou chrb chrc chro chrr chub chur cobb cobh cobo cobu coch coco cocu coho coob cooh cor- corb corc coro corr coub cour crbc crbu crcc crcr crob croc croh croo cror crub cub- cubb cucc curb curo curr hboc hcbc hccb hccc hcch hhhh hobo hoch hocr hoho hoor horc horo horr hour hrob hrrc hubb hubo huch hucu huhu huor huro hurr huru huub obbo obor obrh obro obuh ocbc occc ocro ocrr ocur ohcc ohho ohob ohoh oocr ooho oooh oooo orbb orbo orbu orch orco oro- oror orro orub oucc ouch our- ouro ouu- rbbb rbbr rboh rcbc rcbo rccb rccc rchb rhob rhoc rhoh rob- robb robo robu rocc roch roco rohr rohu roob roor rorc roro roru roub rouh rrrr rubb rubu ruch ruhh ruhr rurc ruro ruru ubbo uboc ucbc ucho ucrc uhoh uhuh uocc uor- urch urho uro- uroo urrh urur uuoc uuuu