-er a-a a-b a-c aaa aab aac aad aae aak aan aar aau ab- aba abb abc abd abe abk abn abr abu ac- aca acb acc acd ace ack acn acr acu ad- ada adb adc add ade adk adn adr adu aea aeb aec aed aee aek aen aer aeu aka akb akc akd ake akk akn akr aku an- ana anb anc and ane ank ann anr anu ar- ara arb arc ard are ark arn arr aru au- aua aub auc aud aue auk aun aur b-u baa bab bac bad bae bak ban bar bau bba bbb bbc bbd bbe bbk bbn bbr bbu bca bcb bcc bcd bce bck bcn bcr bcu bda bdb bdc bdd bde bdk bdr bdu be- bea beb bec bed bee bek ben ber beu bka bkb bkc bke bkk bkn bkr bna bnb bnc bnd bne bnk bnn bnr bnu bra brb brd bre brk brn brr bru bua bub buc bud bue buk bun bur buu c-- caa cab cac cad cae cak can car cau cba cbb cbc cbd cbe cbk cbn cbr cbu cca ccb ccc ccd cce cck ccn ccr ccu cda cdb cdc cdd cde cdk cdn cdr cdu ce- cea ceb cec ced cee cek cen cer ceu cka ckb ckc ckd cn- cna cnb cnc cnd cne cnn cnr cnu cra crb crc crd cre crk crn crr cru cua cub cuc cud cue cuk cun cur cuu daa dab dac dad dae dak dan dar dau dba dbb dbc dbd dbe dbk dbn dbr dbu dca dcb dcc dcd dce dck dcn dcr dcu dda ddb ddc ddd dde ddk ddn ddr ddu de- dea deb dec ded dee dek den der deu dka dkb dkc dke dkk dkr dku dna dnb dnc dnd dne dnk dnn dnr dra drb drc drd dre drk drn drr dru dua dub duc dud due duk dun dur eaa eab eac ead eae eak ean ear eau eba ebb ebc ebd ebe ebk ebn ebr ebu ec- eca ecb ecc ecd ece eck ecn ecr ecu ed- eda edb edc edd ede edk edn edr edu eea eeb eec eed eee eek een eer eka ekb ekc ekd eke ekr eku en- ena enb enc end ene enk enn enr enu era erb erc erd ere erk ern err eru eu- eua eub euc eud eue eun eur ka- kaa kab kac kad kae kak kan kar kau kba kbb kbc kbd kbe kbk kbn kbr kbu kca kcb kcc kcd kce kck kcn kcr kcu kda kdb kdc kde kdk kdr kdu ke- kea keb kec ked kee kek ken ker kkb kkc kke kkk kkn kkr kku kn- kna knc knd kne knk knn knr knu kra krc krd krk krn krr kru kub kuc kud kue kuk kun kur kuu naa nab nac nad nae nak nan nar nau nba nbb nbc nbd nbe nbk nbn nbr nbu nca ncb ncc ncd nce nck ncn ncr ncu nda ndb ndc ndd nde ndk ndn ndr ndu ne- nea neb nec ned nee nek nen ner neu nka nkc nke nkk nkn nkr nku nna nnb nnc nne nnk nnn nnu nra nrb nrc nrd nre nrk nrn nrr nru nua nub nuc nud nue nuk nun nur nuu ra- raa rab rac rad rae rak ran rar rau rba rbb rbc rbd rbe rbk rbn rbr rbu rca rcb rcc rcd rce rcn rcr rcu rda rdb rdc rdd rde rdn rdr rdu re- rea reb rec red ree rek ren rer reu rkb rkc rke rkk rku rna rnb rnc rnd rnn rnr rnu rra rrb rrc rrd rrk rrn rrr rru rua rub ruc rud rue ruk run rur ruu ua- uaa uab uac uad uae uak uan uar uau uba ubb ubc ube ubk ubn ubr ubu uca ucb ucc ucd uce uck ucn ucr ucu uda udb udc udd ude udk udn udr udu uea ueb uec ued uee uen uer uka ukb ukc uke ukk ukn ukr uku un- una unb unc und une unk unn unr unu ur- ura urb urc urd ure urk urn urr uru uua uuc uue uun uur uuu