-al -ol a-a a-b aaa aab aal aao aar aav ab- aba abb abl abo abr abv al- ala alb all alo alr alv aoa aob aol aoo aor aov ar- ara arb arl aro arr arv av- ava avb avl avo avr baa bab bal bao bar bav bba bbb bbl bbo bbr bla blb bll blo blr blv boa bob bol boo bor bov bra brb brl bro brr brv bva bvb bvl bvo bvr bvv la- laa lab lal lao lar lav lba lbb lbl lbo lbr lbv lla llb lll llo llr llv loa lob lol loo lor lov lra lrb lro lrr lrv lva lvb lvl lvr lvv oaa oab oal oao oar oav ob- oba obb obl obo obr obv ola olb oll olo oo- ooa oob ool ooo oor oov or- ora orb orl oro orr orv ov- ova ovb ovl ovo ovv ra- raa rab ral rao rar rav rba rbb rbl rbo rbr rla rll rlo rlr roa rob rol roo ror rov rra rrb rrl rrr rva rvb rvl rvo rvr rvv v-a vaa vab val vao var vav vba vbl vbo vbr vbv vl- vla vlb vll vlo vlv voa vob vol voo vor vov vra vrb vrr vva vvb vvo vvr vvv