a-a a-b aaa aab aak aan aau ab- aba abb abk abn abu aka akb akk akn aku an- ana anb ank ann anu au- aua aub auk aun b-u baa bab bak ban bau bba bbb bbk bbn bbu bka bkb bkk bkn bna bnb bnk bnn bnu bua bub buk bun buu ka- kaa kab kak kan kau kba kbb kbk kbn kbu kkb kkk kkn kku kn- kna knk knn knu kub kuk kun kuu naa nab nak nan nau nba nbb nbk nbn nbu nka nkk nkn nku nna nnb nnk nnn nnu nua nub nuk nun nuu ua- uaa uab uak uan uau uba ubb ubk ubn ubu uka ukb ukk ukn uku un- una unb unk unn unu uua uun uuu