a-a a-b aaa aab aag aan aar aav ab- aba abb abg abn abr abv ag- aga agb agg agn agr agv an- ana anb ang ann anr anv ar- ara arb arg arn arr arv av- ava avb avg avn avr baa bab bag ban bar bav bba bbb bbg bbn bbr bga bgb bgg bgn bgr bgv bna bnb bng bnn bnr bnv bra brb brg brn brr brv bva bvb bvg bvn bvr bvv gaa gab gag gan gar gav gba gbg gbn gbr gbv gga ggb ggg ggn ggr ggv gna gnb gnn gnr gnv gra grb grg grn grr grv gva gvb gvg gvn gvr naa nab nag nan nar nav nba nbb nbg nbn nbr nbv nga ngb ngg ngn nna nnb nng nnn nnv nra nrb nrg nrn nrr nrv nva nvb nvg nvn nvv ra- raa rab rag ran rar rav rba rbb rbg rbn rbr rga rgb rgg rgn rgr rgv rna rnb rng rnn rnr rnv rra rrb rrg rrn rrr rva rvb rvg rvn rvr rvv v-a vaa vab vag van var vav vba vbg vbr vbv vga vgg vgn vgr vn- vna vng vnr vnv vra vrb vrg vrn vrr vva vvb vvg vvr vvv