a-a a-b a-z aaa aab aad aao aar aav aaz ab- aba abb abd abo abr abv abz ad- ada adb add ado adr adv adz aoa aob aod aoo aor aov ar- ara arb ard aro arr arv arz av- ava avb avd avo avr avz az- aza azb azd azo azz baa bab bad bao bar bav baz bba bbb bbd bbo bbr bda bdb bdd bdo bdr bdv bdz boa bob bod boo bor bov boz bra brb brd bro brr brv brz bva bvb bvd bvo bvr bvv bza bzd bzo bzr bzz daa dab dad dao dar dav daz dba dbb dbd dbo dbr dbv dbz dda ddb ddd ddo ddr ddz doa dob dod doo dor dov doz dra drb drd dro drr drv drz dva dvb dvd dvr dza dzb dzd dzo dzr oaa oab oad oao oar oav ob- oba obb obd obo obr obv oda odb odd odo odr odv oo- ooa oob ood ooo oor oov or- ora orb ord oro orr orv orz ov- ova ovb ovd ovo ovv oza ozo ozz ra- raa rab rad rao rar rav raz rba rbb rbd rbo rbr rda rdb rdd rdo rdr rdv roa rob rod roo ror rov roz rra rrb rrd rrr rva rvb rvd rvo rvr rvv rza rzb rzo v-a vaa vab vad vao var vav vaz vba vbd vbo vbr vbv vbz vdb vdd vdo vdr vdv voa vob vod voo vor vov voz vra vrb vrd vrr vva vvb vvo vvr vvv vvz zaa zab zad zao zar zav zaz zbb zbr zbv zdv zo- zoa zob zod zoo zor zro zzr zzz