a-a a-b aaa aab aag aak aau ab- aba abb abg abk abu ag- aga agb agg agk agu aka akb akg akk aku au- aua aub aug auk b-u baa bab bag bak bau bba bbb bbg bbk bbu bga bgb bgg bgk bgu bka bkb bkg bkk bua bub bug buk buu gaa gab gag gak gau gba gbg gbk gbu gga ggb ggg ggu gka gkb gu- gua gub gug guk guu ka- kaa kab kag kak kau kba kbb kbk kbu kga kgb kgu kkb kkk kku kub kug kuk kuu ua- uaa uab uag uak uau uba ubb ubg ubk ubu uga ugb ugg ugk ugu uka ukb ukk uku uua uug uuu