bbbb bbci bbfc bbrc bcbc bccc bcci bcfc bcof bcor bibb bibi bibo bicc bici bico biff bifi bio- bioc bioi birb biri biro birr bobb bobi bobo boco boff boi- boii boob booc boof boor bor- borf bori boro borr brcb brfc bric brio brob broc broo bror brrr c-bo cbbc cbcc cbcr cbfb cbfc cbir ccbc cccb cccc cccf ccci ccfc ccff ccfi ccic ccii ccir ccob ccoc ccrc ccrf ccri cfbc cfbr cfcb cfcf cfco cffb cffr cfor cfrb cibc cibi cibo cicc cici cico cicr ciff ciii ciob cior cirb circ ciri ciro cirr cobb cobi cobo coco cofc coff cofi coif coir coob coof cor- corb corc corf cori coro corr crbc crcc crcr crfc crib cric crif crob croc croo cror fccf fcic fcii ffcc ffff ffii ffrr ficc fico fifc fiff fifi fifo fiii fior foci foco fofo foof for- forb fori foro forr frbc frcc frfc frib fric frio frob ibfi ibrc ibri ibro icbc iccb iccc iccf icci icco iccr icfb icoc icor icrc icrf icrr ifbb ifco ific ifor ifrb ifrf ifri iiii iiio iioi iioo iirc iobi ioci iofc ioii ioio ioof iooi iooo iori ircc iri- iric irio irob iroc irrc irri obbo oboi obor obri obro ocbc occc occi ocro ocrr ofcr off- offc offo offr ofor oici oiii oobi oocr ooff oooo orbb orbi orbo orci orco orff orfi ori- oric orif orio oro- orof oror orri orro rbbb rbbr rcbc rcbo rccb rccc rcfc rcic rffc rfic rib- ribo ricc rico riff riif riri rob- robb robi robo rocc roco rofc roff rofo roif roio roir roob roof rooi roor rorc rori roro rrfc rrif rrrr