-er a-a a-b aaa aab aae aaf aah aan aao aar ab- aba abb abe abf abh abn abo abr aea aeb aee aef aeh aen aeo aer af- afa afb afe aff afh afn afo afr aha ahb ahe ahf ahh ahn aho ahr an- ana anb ane anf anh ann ano anr aoa aob aoe aof aoh aon aoo aor ar- ara arb are arf arh arn aro arr baa bab bae baf bah ban bao bar bba bbb bbe bbf bbh bbn bbo bbr be- bea beb bee bef beh ben beo ber bfa bfb bfe bff bfh bfn bfo bfr bha bhb bhe bhf bhh bho bhr bna bnb bne bnf bnn bno bnr boa bob boe bof boh bon boo bor bra brb bre brf brh brn bro brr eaa eab eae eaf eah ean eao ear eba ebb ebe ebf ebh ebn ebo ebr eea eeb eee eef een eeo eer ef- efa efb efe eff efh efo efr eha ehb ehe ehf ehh ehn eho ehr en- ena enb ene enf enh enn eno enr eo- eoa eob eoe eof eoh eon eoo eor era erb ere erf erh ern ero err faa fab fae faf fah fan fao far fba fbb fbe fbf fbh fbn fbo fbr fea feb fee fef feh fen feo fer ffa ffe fff ffh ffn ffo ffr fha fhb fhe fhf fhh fhn fho fhr fna fnb fne fnf fnh fnn fnr foa fob foe fof foh fon foo for fra frb fre frf frh frn fro frr haa hab hae haf hah han hao har hba hbb hbe hbf hbh hbn hbo hbr he- hea heb hee hef heh hen heo her hfa hfb hfe hff hfh hfn hfo hfr hha hhb hhe hhf hhh hhn hho hhr hna hnb hne hnf hnh hnn hno hoa hob hoe hof hoh hon hoo hor hr- hra hrb hre hrf hrh hrn hro hrr naa nab nae naf nah nan nao nar nba nbb nbe nbf nbn nbo nbr ne- nea neb nee nef neh nen neo ner nfa nfb nfe nff nfn nfo nfr nha nhb nhe nhf nhh nhn nhr nna nnb nne nnf nnh nnn nno no- noa nob noe nof noh non noo nor nra nrb nre nrf nrn nro nrr oaa oab oae oaf oah oan oao oar ob- oba obb obe obf obh obn obo obr oea oeb oee oef oeh oen oeo oer of- ofa ofb ofe off ofn ofo ofr oha ohe ohf ohh ohn oho ohr on- ona onb one onf onh onn ono onr oo- ooa oob oof ooh oon ooo oor or- ora orb ore orf orh orn oro orr ra- raa rab rae raf rah ran rao rar rba rbb rbe rbf rbh rbn rbo rbr re- rea reb ree ref reh ren reo rer rfa rfb rfe rff rfh rfn rfo rfr rh- rha rhb rhe rhf rhh rhn rho rhr rna rnb rnh rnn rno rnr roa rob roe rof roh ron roo ror rra rrb rrf rrh rrn rrr