-er a-a a-b aaa aab aad aae aan aao aar aau ab- aba abb abd abe abn abo abr abu ad- ada adb add ade adn ado adr adu aea aeb aed aee aen aeo aer aeu an- ana anb and ane ann ano anr anu aoa aob aod aoe aon aoo aor aou ar- ara arb ard are arn aro arr aru au- aua aub aud aue aun auo aur b-u baa bab bad bae ban bao bar bau bba bbb bbd bbe bbn bbo bbr bbu bda bdb bdd bde bdo bdr bdu be- bea beb bed bee ben beo ber beu bna bnb bnd bne bnn bno bnr bnu boa bob bod boe bon boo bor bou bra brb brd bre brn bro brr bru bua bub bud bue bun buo bur buu daa dab dad dae dan dao dar dau dba dbb dbd dbe dbn dbo dbr dbu dda ddb ddd dde ddn ddo ddr ddu de- dea deb ded dee den deo der deu dna dnb dnd dne dnn dno dnr doa dob dod doe don doo dor dou dra drb drd dre drn dro drr dru dua dub dud due dun duo dur eaa eab ead eae ean eao ear eau eba ebb ebd ebe ebn ebo ebr ebu ed- eda edb edd ede edn edo edr edu eea eeb eed eee een eeo eer en- ena enb end ene enn eno enr enu eo- eoa eob eod eoe eon eoo eor eou era erb erd ere ern ero err eru eu- eua eub eud eue eun eur naa nab nad nae nan nao nar nau nba nbb nbd nbe nbn nbo nbr nbu nda ndb ndd nde ndn ndo ndr ndu ne- nea neb ned nee nen neo ner neu nna nnb nne nnn nno nnu no- noa nob nod noe non noo nor nou nra nrb nrd nre nrn nro nrr nru nua nub nud nue nun nuo nur nuu oaa oab oad oae oan oao oar oau ob- oba obb obd obe obn obo obr obu oda odb odd ode odn odo odr odu oea oeb oed oee oen oeo oer on- ona onb ond one onn ono onr onu oo- ooa oob ood oon ooo oor or- ora orb ord ore orn oro orr oru ou- oua oud oue oun ouo our ra- raa rab rad rae ran rao rar rau rba rbb rbd rbe rbn rbo rbr rbu rda rdb rdd rde rdn rdo rdr rdu re- rea reb red ree ren reo rer reu rna rnb rnd rnn rno rnr rnu roa rob rod roe ron roo ror rou rra rrb rrd rrn rrr rru rua rub rud rue run ruo rur ruu ua- uaa uab uad uae uan uao uar uau uba ubb ube ubn ubo ubr ubu uda udb udd ude udn udo udr udu uea ueb ued uee uen uer un- una unb und une unn uno unr unu uoa uob uod uoe uon uoo uor ur- ura urb urd ure urn uro urr uru uua uue uun uur uuu