-er -ey a-a a-b aaa aab aae aak aao aar aay ab- aba abb abe abk abo abr aby aea aeb aee aek aeo aer aey aka akb ake akk ako akr aoa aob aoe aok aoo aor ar- ara arb are ark aro arr ary ay- aya aye ayk ayo ayr baa bab bae bak bao bar bay bba bbb bbe bbk bbo bbr bby be- bea beb bee bek beo ber bey bka bkb bke bkk bko bkr boa bob boe bok boo bor boy bra brb bre brk bro brr bry by- bya bye byk byo byr eaa eab eae eak eao ear eba ebb ebe ebk ebo ebr eby eea eeb eee eek eeo eer eey eka ekb eke eko ekr eky eo- eoa eob eoe eok eoo eor era erb ere erk ero err ery eya eye eyo eyr ka- kaa kab kae kak kao kar kay kba kbb kbe kbk kbo kbr ke- kea keb kee kek keo ker key kkb kke kkk kkr kky koa kob koe kok koo kor koy kra krk kro krr kry kya kye kyo kyr oaa oab oae oak oao oar ob- oba obb obe obk obo obr oby oea oeb oee oeo oer oey oka okb oke okk oko okr oo- ooa oob ook ooo oor or- ora orb ore ork oro orr ory oya oye oyo ra- raa rab rae rak rao rar ray rba rbb rbe rbk rbo rbr re- rea reb ree rek reo rer rey rkb rke rkk rko rky roa rob roe rok roo ror roy rra rrb rrk rrr ry- rya rye ryk ryo ryr ryy yaa yab yae yak yao yar yay ybe ybr yby yea yeb yee yek yeo yer yey yka ykk yob yoe yok yoo yor yoy yra yre yro yyb yye yyy