-al -ol a-a a-b aaa aab aaf aag aal aao aar ab- aba abb abf abg abl abo abr af- afa afb aff afg afl afo afr ag- aga agb agf agg agl ago agr al- ala alb alf alg all alo alr aoa aob aof aog aol aoo aor ar- ara arb arf arg arl aro arr baa bab baf bag bal bao bar bba bbb bbf bbg bbl bbo bbr bfa bfb bff bfg bfl bfo bfr bga bgb bgf bgg bgl bgo bgr bla blb blf blg bll blo blr boa bob bof bog bol boo bor bra brb brf brg brl bro brr faa fab faf fag fal fao far fba fbb fbf fbg fbl fbo fbr ffa fff ffg ffl ffo ffr fga fgb fgf fgg fgl fgr fla flb flf flg fll flo flr foa fob fof fog fol foo for fra frb frf frg frl fro frr gaa gab gaf gag gal gao gar gba gbf gbg gbl gbo gbr gfa gfb gff gfl gfo gfr gga ggb ggg ggo ggr gla glb glf glg gll glo glr goa gob gof gog gol goo gor gra grb grf grg grl gro grr la- laa lab laf lag lal lao lar lba lbb lbf lbg lbl lbo lbr lfa lfb lff lfg lfl lfo lfr lga lgb lgf lgg lgl lgo lgr lla llb llf llg lll llo llr loa lob lof log lol loo lor lra lrb lrf lrg lro lrr oaa oab oaf oag oal oao oar ob- oba obb obf obg obl obo obr of- ofa ofb off ofg ofl ofo ofr oga ogf ogg ogl ogo ola olb olf olg oll olo oo- ooa oob oof oog ool ooo oor or- ora orb orf org orl oro orr ra- raa rab raf rag ral rao rar rba rbb rbf rbg rbl rbo rbr rfa rfb rff rfg rfl rfo rfr rga rgb rgf rgg rgo rgr rla rlf rlg rll rlo rlr roa rob rof rog rol roo ror rra rrb rrf rrg rrl rrr