-er a-a a-b a-i aaa aab aad aae aai aak aao aar ab- aba abb abd abe abi abk abo abr ad- ada adb add ade adi adk ado adr aea aeb aed aee aei aek aeo aer ai- aia aib aid aie aii aik aio air aka akb akd ake aki akk ako akr aoa aob aod aoe aoi aok aoo aor ar- ara arb ard are ari ark aro arr baa bab bad bae bai bak bao bar bba bbb bbd bbe bbi bbk bbo bbr bda bdb bdd bde bdi bdk bdo bdr be- bea beb bed bee bei bek beo ber bi- bia bib bid bie bii bik bio bir bka bkb bke bkk bko bkr boa bob bod boe boi bok boo bor bra brb brd bre bri brk bro brr daa dab dad dae dai dak dao dar dba dbb dbd dbe dbi dbk dbo dbr dda ddb ddd dde ddi ddk ddo ddr de- dea deb ded dee dei dek deo der di- dia dib did die dii dik dio dir dka dkb dke dki dkk dko dkr doa dob dod doe doi dok doo dor dra drb drd dre dri drk dro drr eaa eab ead eae eai eak eao ear eba ebb ebd ebe ebi ebk ebo ebr ed- eda edb edd ede edi edk edo edr eea eeb eed eee eek eeo eer eia eib eid eie eii eik eio eir eka ekb ekd eke eki eko ekr eo- eoa eob eod eoe eoi eok eoo eor era erb erd ere eri erk ero err i-d ia- iaa iab iad iae iai iao iar iba ibb ibd ibe ibi ibk ibo ibr ida idb idd ide idi idk ido idr ie- iea ied iee iei iek ier iia iib iid iie iii iio iir ika ikb ike iki ikk iko ikr io- ioa iob iod ioe ioi ioo ior ir- ira irb ird ire iri irk iro irr ka- kaa kab kad kae kai kak kao kar kba kbb kbd kbe kbi kbk kbo kbr kda kdb kde kdk kdo kdr ke- kea keb ked kee kei kek keo ker kia kib kid kie kii kik kio kir kkb kke kki kkk kkr koa kob kod koe koi kok koo kor kra krd kri krk kro krr o-i oaa oab oad oae oai oak oao oar ob- oba obb obd obe obi obk obo obr oda odb odd ode odi odo odr oea oeb oed oee oei oeo oer oia oib oid oie oii oik oio oir oka okb okd oke oki okk oko okr oo- ooa oob ood ooi ook ooo oor or- ora orb ord ore ori ork oro orr ra- raa rab rad rae rai rak rao rar rba rbb rbd rbe rbi rbk rbo rbr rda rdb rdd rde rdi rdo rdr re- rea reb red ree rei rek reo rer ria rib rid rie rii rik rio rir rkb rke rkk rko roa rob rod roe roi rok roo ror rra rrb rrd rri rrk rrr