a-a a-b aaa aab aad aak aao aar aay ab- aba abb abd abk abo abr aby ad- ada adb add adk ado adr ady aka akb akd akk ako akr aoa aob aod aok aoo aor ar- ara arb ard ark aro arr ary ay- aya ayd ayk ayo ayr baa bab bad bak bao bar bay bba bbb bbd bbk bbo bbr bby bda bdb bdd bdk bdo bdr bdy bka bkb bkk bko bkr boa bob bod bok boo bor boy bra brb brd brk bro brr bry by- bya byd byk byo byr daa dab dad dak dao dar day dba dbb dbd dbk dbo dbr dby dda ddb ddd ddk ddo ddr ddy dka dkb dkk dko dkr doa dob dod dok doo dor doy dra drb drd drk dro drr dry dy- dya dyb dyd dyk dyo dyr dyy ka- kaa kab kad kak kao kar kay kba kbb kbd kbk kbo kbr kda kdb kdk kdo kdr kdy kkb kkk kkr kky koa kob kod kok koo kor koy kra krd krk kro krr kry kya kyd kyo kyr oaa oab oad oak oao oar ob- oba obb obd obk obo obr oby oda odb odd odo odr oka okb okd okk oko okr oo- ooa oob ood ook ooo oor or- ora orb ord ork oro orr ory oya oyd oyo ra- raa rab rad rak rao rar ray rba rbb rbd rbk rbo rbr rda rdb rdd rdo rdr rdy rkb rkk rko rky roa rob rod rok roo ror roy rra rrb rrd rrk rrr ry- rya ryd ryk ryo ryr ryy yaa yab yad yak yao yar yay ybr yby yda ydo ydy yka ykk yob yod yok yoo yor yoy yra yro yyb yyy