-er -ey a-a a-b a-c aaa aab aac aae aak aao aar aay ab- aba abb abc abe abk abo abr aby ac- aca acb acc ace ack aco acr acy aea aeb aec aee aek aeo aer aey aka akb akc ake akk ako akr aoa aob aoc aoe aok aoo aor ar- ara arb arc are ark aro arr ary ay- aya ayc aye ayk ayo ayr baa bab bac bae bak bao bar bay bba bbb bbc bbe bbk bbo bbr bby bca bcb bcc bce bck bco bcr bcy be- bea beb bec bee bek beo ber bey bka bkb bkc bke bkk bko bkr boa bob boc boe bok boo bor boy bra brb bre brk bro brr bry by- bya byc bye byk byo byr c-- caa cab cac cae cak cao car cay cba cbb cbc cbe cbk cbo cbr cby cca ccb ccc cce cck cco ccr ce- cea ceb cec cee cek ceo cer cey cka ckb ckc cko cky co- coa cob coc coe cok coo cor coy cra crb crc cre crk cro crr cry cya cyb cyc cye cyk cyo cyr eaa eab eac eae eak eao ear eba ebb ebc ebe ebk ebo ebr eby ec- eca ecb ecc ece eck eco ecr eea eeb eec eee eek eeo eer eey eka ekb ekc eke eko ekr eky eo- eoa eob eoc eoe eok eoo eor era erb erc ere erk ero err ery eya eyc eye eyo eyr ka- kaa kab kac kae kak kao kar kay kba kbb kbc kbe kbk kbo kbr kca kcb kcc kce kck kcr ke- kea keb kec kee kek keo ker key kkb kkc kke kkk kkr kky koa kob koc koe kok koo kor koy kra krc krk kro krr kry kya kyc kye kyo kyr oaa oab oac oae oak oao oar ob- oba obb obc obe obk obo obr oby oc- oca ocb occ ock oco ocr oea oeb oec oee oeo oer oey oka okb okc oke okk oko okr oo- ooa oob ooc ook ooo oor or- ora orb orc ore ork oro orr ory oya oye oyo ra- raa rab rac rae rak rao rar ray rba rbb rbc rbe rbk rbo rbr rca rcb rcc rce rco rcr re- rea reb rec ree rek reo rer rey rkb rkc rke rkk rko rky roa rob roc roe rok roo ror roy rra rrb rrc rrk rrr ry- rya ryc rye ryk ryo ryr ryy yaa yab yac yae yak yao yar yay ybc ybe ybr yby yca ycc yce yco ycy yea yeb yec yee yek yeo yer yey yka ykk yob yoc yoe yok yoo yor yoy yra yrc yre yro yyb yyc yye yyy