-er -ey bbb bbc bbe bbk bbo bbr bbt bby bcb bcc bce bck bco bcr bct bcy be- beb bec bee bek beo ber bet bey bkb bkc bke bkk bko bkr bkt bob boc boe bok boo bor bot boy brb bre brk bro brr brt bry btb btc bte btk bto btr btt bty by- byc bye byk byo byr byt c-- cbb cbc cbe cbk cbo cbr cbt cby ccb ccc cce cck cco ccr cct ce- ceb cec cee cek ceo cer cet cey ckb ckc cko ckt cky co- cob coc coe cok coo cor cot coy crb crc cre crk cro crr crt cry ctb ctc cte ctk cto ctr ctt cty cyb cyc cye cyk cyo cyr cyt ebb ebc ebe ebk ebo ebr ebt eby ec- ecb ecc ece eck eco ecr ect eeb eec eee eek eeo eer eet eey ekb ekc eke eko ekr ekt eky eo- eob eoc eoe eok eoo eor eot erb erc ere erk ero err ert ery etb etc ete etk eto etr ett ety eyc eye eyo eyr eyt k-t kbb kbc kbe kbk kbo kbr kcb kcc kce kck kcr kct ke- keb kec kee kek keo ker ket key kkb kkc kke kkk kkr kkt kky kob koc koe kok koo kor kot koy krc krk kro krr krt kry ktb ktc kte ktk kto ktr ktt kyc kye kyo kyr kyt ob- obb obc obe obk obo obr obt oby oc- ocb occ ock oco ocr oct oeb oec oee oeo oer oet oey okb okc oke okk oko okr oo- oob ooc ook ooo oor oot or- orb orc ore ork oro orr ort ory ot- otb otc ote otk oto otr ott oye oyo rbb rbc rbe rbk rbo rbr rbt rcb rcc rce rco rcr rct re- reb rec ree rek reo rer ret rey rkb rkc rke rkk rko rkt rky rob roc roe rok roo ror rot roy rrb rrc rrk rrr rrt rtb rtc rte rtk rto rtr rtt rty ry- ryc rye ryk ryo ryr ryy tbb tbc tbe tbk tbo tbr tbt tcb tcc tce tck tco tcr tct te- teb tec tee tek teo ter tet tey tkb tkc tke tkk tko tkr tkt tky to- tob toc toe tok too tor tot toy trb trc tre trk tro trr trt try ttb ttc tte ttk tto ttr ttt tty tyc tye tyo tyr tyt ybc ybe ybr yby ycc yce yco ycy yeb yec yee yek yeo yer yet yey ykk yob yoc yoe yok yoo yor yot yoy yrc yre yro yrt ytc yte ytk yto ytr ytt yyb yyc yye yyt yyy