-er a-a a-b a-t aaa aab aae aak aao aar aat aau ab- aba abb abe abk abo abr abt abu aea aeb aee aek aeo aer aet aeu aka akb ake akk ako akr aku aoa aob aoe aok aoo aor aot aou ar- ara arb are ark aro arr art aru at- ata atb ate ato atr att atu au- aua aub aue auk auo aur aut b-u baa bab bae bak bao bar bat bau bba bbb bbe bbk bbo bbr bbt bbu be- bea beb bee bek beo ber bet beu bka bkb bke bkk bko bkr bkt boa bob boe bok boo bor bot bou bra brb bre brk bro brr brt bru bta btb bte btk bto btr btt btu bua bub bue buk buo bur but buu eaa eab eae eak eao ear eat eau eba ebb ebe ebk ebo ebr ebt ebu eea eeb eee eek eeo eer eet eka ekb eke eko ekr ekt eku eo- eoa eob eoe eok eoo eor eot eou era erb ere erk ero err ert eru eta etb ete etk eto etr ett etu eu- eua eub eue eur eut k-t ka- kaa kab kae kak kao kar kat kau kba kbb kbe kbk kbo kbr kbu ke- kea keb kee kek keo ker ket kkb kke kkk kkr kkt kku koa kob koe kok koo kor kot kou kra krk kro krr krt kru kta ktb kte ktk kto ktr ktt ktu kub kue kuk kur kut kuu oaa oab oae oak oao oar oat oau ob- oba obb obe obk obo obr obt obu oea oeb oee oeo oer oet oka okb oke okk oko okr oku oo- ooa oob ook ooo oor oot or- ora orb ore ork oro orr ort oru ot- ota otb ote otk oto otr ott otu ou- oua oue ouk ouo our out ra- raa rab rae rak rao rar rat rau rba rbb rbe rbk rbo rbr rbt rbu re- rea reb ree rek reo rer ret reu rkb rke rkk rko rkt rku roa rob roe rok roo ror rot rou rra rrb rrk rrr rrt rru rta rtb rte rtk rto rtr rtt rtu rua rub rue ruk ruo rur rut ruu taa tab tae tak tao tar tat tau tba tbb tbe tbk tbo tbr tbt tbu te- tea teb tee tek teo ter tet teu tka tkb tke tkk tko tkr tkt to- toa tob toe tok too tor tot tou tra trb tre trk tro trr trt tru tta ttb tte ttk tto ttr ttt ttu tua tub tue tuk tuo tur tut tuu ua- uaa uab uae uak uao uar uat uau uba ubb ube ubk ubo ubr ubt ubu uea ueb uee uer uet uka ukb uke ukk ukr uku uoa uob uoe uok uoo uor uot ur- ura urb ure urk uro urr urt uru uta utb ute utk uto utr utt utu uua uue uur uut uuu