bbb bbk bbo bbs bbw bby bkb bkk bko bks bkw bob bok boo bos bow boy boz bsb bsk bso bss bsw bsy bwb bwk bwo bws bwy by- byk byo bys byz bzo bzs bzz k-z kbb kbk kbo kbs kbw kbz kkb kkk kks kky kob kok koo kos kow koy koz ksb ksk kso kss ksw kw- kwk kwo kws kww kyo kys kyw kyz kzo kzw kzy ob- obb obk obo obs obw oby okb okk oko oks okw oo- oob ook ooo oos oow os- osb osk oso oss osw owb owk owo ows oww oyo oys ozo ozs ozw ozz sbb sbk sbo sbs sbw sby sk- skb skk sko sks skw sky sob sok soo sos sow soy soz ss- ssb ssk sso sss ssw ssz swb swk swo sws swy sy- syb syk sys wbb wbo wbs wbw wbz wkb wko wks wkw wky wob wok woo wos wow woy woz wsb wsk wso wss wsw wwo www wy- wyk wyo wys ybs yby ybz ykk yob yok yoo yos yow yoy ysb ysk yso yss ysy ysz yyb yys yyy yyz yzb yzy zbb zbs zbw zby zks zo- zob zok zoo zos zow zsz zws zzs zzy zzz