-er a-a a-b a-i a-t aaa aab aae aaf aai aan aao aar aat ab- aba abb abe abf abi abn abo abr abt aea aeb aee aef aei aen aeo aer aet af- afa afb afe aff afi afn afo afr aft ai- aia aib aie aif aii ain aio air ait an- ana anb ane anf ani ann ano anr ant aoa aob aoe aof aoi aon aoo aor aot ar- ara arb are arf ari arn aro arr art at- ata atb ate atf ati atn ato atr att baa bab bae baf bai ban bao bar bat bba bbb bbe bbf bbi bbn bbo bbr bbt be- bea beb bee bef bei ben beo ber bet bfa bfb bfe bff bfi bfn bfo bfr bft bi- bia bib bie bif bii bin bio bir bit bna bnb bne bnf bni bnn bno bnr bnt boa bob boe bof boi bon boo bor bot bra brb bre brf bri brn bro brr brt bta btb bte btf bti btn bto btr btt eaa eab eae eaf eai ean eao ear eat eba ebb ebe ebf ebi ebn ebo ebr ebt eea eeb eee eef een eeo eer eet ef- efa efb efe eff efi efo efr eft eia eib eie eif eii ein eio eir eit en- ena enb ene enf eni enn eno enr ent eo- eoa eob eoe eof eoi eon eoo eor eot era erb ere erf eri ern ero err ert eta etb ete etf eti etn eto etr ett faa fab fae faf fai fan fao far fat fba fbb fbe fbf fbi fbn fbo fbr fbt fea feb fee fef fei fen feo fer fet ffa ffe fff ffi ffn ffo ffr fft fia fib fie fif fii fin fir fit fna fnb fne fnf fni fnn fnr fnt foa fob foe fof foi fon foo for fot fra frb fre frf fri frn fro frr frt fta ftb fte ftf fti ftn fto ftr ftt i-f ia- iaa iab iae iaf iai ian iao iar iat iba ibb ibe ibf ibi ibn ibo ibr ibt ie- iea iee ief iei ien ier iet ifa ifb ife iff ifi ifn ifo ifr ift iia iib iie iif iii iin iio iir iit in- ina inb ine inf ini inn ino inr int io- ioa iob ioe iof ioi ion ioo ior iot ir- ira irb ire irf iri irn iro irr irt ita itb ite itf iti itn ito itt n-i naa nab nae naf nai nan nao nar nat nba nbb nbe nbf nbi nbn nbo nbr nbt ne- nea neb nee nef nei nen neo ner net nfa nfb nfe nff nfi nfn nfo nfr nft nia nib nie nif nii nin nio nir nit nna nnb nne nnf nni nnn nno nnt no- noa nob noe nof noi non noo nor not nra nrb nre nrf nri nrn nro nrr nrt nta ntb nte ntf nti ntn nto ntr ntt o-i oaa oab oae oaf oai oan oao oar oat ob- oba obb obe obf obi obn obo obr obt oea oeb oee oef oei oen oeo oer oet of- ofa ofb ofe off ofi ofn ofo ofr oft oia oib oie oif oii oin oio oir oit on- ona onb one onf oni onn ono onr ont oo- ooa oob oof ooi oon ooo oor oot or- ora orb ore orf ori orn oro orr ort ot- ota otb ote otf oti otn oto otr ott ra- raa rab rae raf rai ran rao rar rat rba rbb rbe rbf rbi rbn rbo rbr rbt re- rea reb ree ref rei ren reo rer ret rfa rfb rfe rff rfi rfn rfo rfr rft ria rib rie rif rii rin rio rir rit rna rnb rni rnn rno rnr rnt roa rob roe rof roi ron roo ror rot rra rrb rrf rri rrn rrr rrt rta rtb rte rtf rti rtn rto rtr rtt taa tab tae taf tai tan tao tar tat tba tbb tbe tbf tbi tbn tbo tbr tbt te- tea teb tee tef tei ten teo ter tet tfa tfb tfe tff tfi tfn tfo tfr tft tia tib tie tif tii tin tio tir tit tna tnb tne tnf tni tnn tno tnr tnt to- toa tob toe tof toi ton too tor tot tra trb tre trf tri trn tro trr trt tta ttb tte ttf tti ttn tto ttr ttt