-er a-a a-b a-c a-t aaa aab aac aae aak aao aar aat aau ab- aba abb abc abe abk abo abr abt abu ac- aca acb acc ace ack aco acr act acu aea aeb aec aee aek aeo aer aet aeu aka akb akc ake akk ako akr aku aoa aob aoc aoe aok aoo aor aot aou ar- ara arb arc are ark aro arr art aru at- ata atb atc ate ato atr att atu au- aua aub auc aue auk auo aur aut b-u baa bab bac bae bak bao bar bat bau bba bbb bbc bbe bbk bbo bbr bbt bbu bca bcb bcc bce bck bco bcr bct bcu be- bea beb bec bee bek beo ber bet beu bka bkb bkc bke bkk bko bkr bkt boa bob boc boe bok boo bor bot bou bra brb bre brk bro brr brt bru bta btb btc bte btk bto btr btt btu bua bub buc bue buk buo bur but buu c-- caa cab cac cae cak cao car cat cau cba cbb cbc cbe cbk cbo cbr cbt cbu cca ccb ccc cce cck cco ccr cct ccu ce- cea ceb cec cee cek ceo cer cet ceu cka ckb ckc cko ckt co- coa cob coc coe cok coo cor cot cou cra crb crc cre crk cro crr crt cru cta ctb ctc cte ctk cto ctr ctt ctu cua cub cuc cue cuk cuo cur cut cuu eaa eab eac eae eak eao ear eat eau eba ebb ebc ebe ebk ebo ebr ebt ebu ec- eca ecb ecc ece eck eco ecr ect ecu eea eeb eec eee eek eeo eer eet eka ekb ekc eke eko ekr ekt eku eo- eoa eob eoc eoe eok eoo eor eot eou era erb erc ere erk ero err ert eru eta etb etc ete etk eto etr ett etu eu- eua eub euc eue eur eut k-t ka- kaa kab kac kae kak kao kar kat kau kba kbb kbc kbe kbk kbo kbr kbu kca kcb kcc kce kck kcr kct kcu ke- kea keb kec kee kek keo ker ket kkb kkc kke kkk kkr kkt kku koa kob koc koe kok koo kor kot kou kra krc krk kro krr krt kru kta ktb ktc kte ktk kto ktr ktt ktu kub kuc kue kuk kur kut kuu oaa oab oac oae oak oao oar oat oau ob- oba obb obc obe obk obo obr obt obu oc- oca ocb occ ock oco ocr oct ocu oea oeb oec oee oeo oer oet oka okb okc oke okk oko okr oku oo- ooa oob ooc ook ooo oor oot or- ora orb orc ore ork oro orr ort oru ot- ota otb otc ote otk oto otr ott otu ou- oua ouc oue ouk ouo our out ra- raa rab rac rae rak rao rar rat rau rba rbb rbc rbe rbk rbo rbr rbt rbu rca rcb rcc rce rco rcr rct rcu re- rea reb rec ree rek reo rer ret reu rkb rkc rke rkk rko rkt rku roa rob roc roe rok roo ror rot rou rra rrb rrc rrk rrr rrt rru rta rtb rtc rte rtk rto rtr rtt rtu rua rub ruc rue ruk ruo rur rut ruu taa tab tac tae tak tao tar tat tau tba tbb tbc tbe tbk tbo tbr tbt tbu tca tcb tcc tce tck tco tcr tct tcu te- tea teb tec tee tek teo ter tet teu tka tkb tkc tke tkk tko tkr tkt to- toa tob toc toe tok too tor tot tou tra trb trc tre trk tro trr trt tru tta ttb ttc tte ttk tto ttr ttt ttu tua tub tuc tue tuk tuo tur tut tuu ua- uaa uab uac uae uak uao uar uat uau uba ubb ubc ube ubk ubo ubr ubt ubu uca ucb ucc uce uck uco ucr uct ucu uea ueb uec uee uer uet uka ukb ukc uke ukk ukr uku uoa uob uoc uoe uok uoo uor uot ur- ura urb urc ure urk uro urr urt uru uta utb utc ute utk uto utr utt utu uua uuc uue uur uut uuu