-er a-a a-b aaa aab aae aaj aak aao aar ab- aba abb abe abj abk abo abr aea aeb aee aej aek aeo aer aja ajb aje ajj ajk ajo ajr aka akb ake akj akk ako akr aoa aob aoe aoj aok aoo aor ar- ara arb are arj ark aro arr baa bab bae baj bak bao bar bba bbb bbe bbk bbo bbr be- bea beb bee bek beo ber bja bjj bjk bjr bka bkb bke bkk bko bkr boa bob boe boj bok boo bor bra brb bre brj brk bro brr eaa eab eae eaj eak eao ear eba ebb ebe ebj ebk ebo ebr eea eeb eee eek eeo eer eja ejo eka ekb eke eko ekr eo- eoa eob eoe eok eoo eor era erb ere erk ero err jaa jab jae jaj jak jao jar jba jbj jbk jbo jbr jea jeb jee jej jek jeo jer jja jjb jjj jjk jjr jka jkb jkk jko jkr joa job joe joj jok joo jor jra jrb jrk jro jrr ka- kaa kab kae kaj kak kao kar kba kbb kbe kbk kbo kbr ke- kea keb kee kek keo ker kjb kje kjr kkb kke kkk kkr koa kob koe kok koo kor kra krk kro krr oaa oab oae oaj oak oao oar ob- oba obb obe obj obk obo obr oea oeb oee oeo oer oja ojb oje ojo oka okb oke okj okk oko okr oo- ooa oob ook ooo oor or- ora orb ore ork oro orr ra- raa rab rae raj rak rao rar rba rbb rbe rbk rbo rbr re- rea reb ree rek reo rer rja rjk rjr rkb rke rkk rko roa rob roe roj rok roo ror rra rrb rrk rrr