a-a a-b aaa aab aah aao aar aav ab- aba abb abh abo abr abv aha ahb ahh aho ahr ahv aoa aob aoh aoo aor aov ar- ara arb arh aro arr arv av- ava avb avh avo avr baa bab bah bao bar bav bba bbb bbh bbo bbr bha bhb bhh bho bhr bhv boa bob boh boo bor bov bra brb brh bro brr brv bva bvb bvh bvo bvr bvv haa hab hah hao har hav hba hbb hbh hbo hbr hbv hha hhb hhh hho hhr hhv hoa hob hoh hoo hor hov hr- hra hrb hrh hro hrr hrv hv- hva hvb hvo hvr hvv oaa oab oah oao oar oav ob- oba obb obh obo obr obv oha ohh oho ohr oo- ooa oob ooh ooo oor oov or- ora orb orh oro orr orv ov- ova ovb ovh ovo ovv ra- raa rab rah rao rar rav rba rbb rbh rbo rbr rh- rha rhb rhh rho rhr rhv roa rob roh roo ror rov rra rrb rrh rrr rva rvb rvh rvo rvr rvv v-a vaa vab vah vao var vav vba vbh vbo vbr vbv vh- vha vhb vho voa vob voh voo vor vov vra vrb vrh vrr vva vvb vvo vvr vvv