-er a-a a-b a-i a-z aaa aab aae aai aak aao aar aaz ab- aba abb abe abi abk abo abr abz aea aeb aee aei aek aeo aer aez ai- aia aib aie aii aik aio air aiz aka akb ake aki akk ako akr aoa aob aoe aoi aok aoo aor ar- ara arb are ari ark aro arr arz az- aza azb aze azi azo azz baa bab bae bai bak bao bar baz bba bbb bbe bbi bbk bbo bbr be- bea beb bee bei bek beo ber bez bi- bia bib bie bii bik bio bir biz bka bkb bke bkk bko bkr boa bob boe boi bok boo bor boz bra brb bre bri brk bro brr brz bza bze bzo bzr bzz eaa eab eae eai eak eao ear eaz eba ebb ebe ebi ebk ebo ebr eea eeb eee eek eeo eer eia eib eie eii eik eio eir eka ekb eke eki eko ekr eo- eoa eob eoe eoi eok eoo eor era erb ere eri erk ero err erz eze ezo ezr ezz ia- iaa iab iae iai iao iar iaz iba ibb ibe ibi ibk ibo ibr ibz ie- iea iee iei iek ier iia iib iie iii iio iir ika ikb ike iki ikk iko ikr io- ioa iob ioe ioi ioo ior ir- ira irb ire iri irk iro irr iza ize izi izo izz k-z ka- kaa kab kae kai kak kao kar kaz kba kbb kbe kbi kbk kbo kbr kbz ke- kea keb kee kei kek keo ker kez kia kib kie kii kik kio kir kiz kkb kke kki kkk kkr koa kob koe koi kok koo kor koz kra kri krk kro krr kzo o-i oaa oab oae oai oak oao oar ob- oba obb obe obi obk obo obr oea oeb oee oei oeo oer oia oib oie oii oik oio oir oiz oka okb oke oki okk oko okr oo- ooa oob ooi ook ooo oor or- ora orb ore ori ork oro orr orz oza oze ozo ozz ra- raa rab rae rai rak rao rar raz rba rbb rbe rbi rbk rbo rbr re- rea reb ree rei rek reo rer rez ria rib rie rii rik rio rir riz rkb rke rkk rko rkz roa rob roe roi rok roo ror roz rra rrb rri rrk rrr rza rzb rze rzo zaa zab zai zak zao zar zaz zbb zbr zea zeb zee zek zeo zer zez zia zib zie zik zio zir ziz zka zo- zoa zob zoe zoi zok zoo zor zro zzr zzz