a-a a-b a-t aaa aab aag aat aau ab- aba abb abg abt abu ag- aga agb agg agt agu at- ata atb atg att atu au- aua aub aug aut b-u baa bab bag bat bau bba bbb bbg bbt bbu bga bgb bgg bgt bgu bta btb btg btt btu bua bub bug but buu gaa gab gag gat gau gba gbg gbt gbu gga ggb ggg ggt ggu gta gtb gtg gtt gtu gu- gua gub gug gut guu taa tab tag tat tau tba tbb tbg tbt tbu tga tgb tgg tgt tgu tta ttb ttg ttt ttu tua tub tug tut tuu ua- uaa uab uag uat uau uba ubb ubg ubt ubu uga ugb ugg ugt ugu uta utb utt utu uua uug uut uuu