a-a a-b a-t aaa aab aan aas aat aau ab- aba abb abn abs abt abu an- ana anb ann ans ant anu as- asa asb asn ass ast asu at- ata atb atn ats att atu au- aua aub aun aus aut b-u baa bab ban bas bat bau bba bbb bbn bbs bbt bbu bna bnb bnn bns bnt bnu bsa bsb bsn bss bst bsu bta btb btn bts btt btu bua bub bun bus but buu naa nab nan nas nat nau nba nbb nbn nbs nbt nbu nna nnb nnn nns nnt nnu nsa nsb nsn nss nst nsu nta ntb ntn nts ntt ntu nua nub nun nus nut nuu saa sab san sas sat sau sba sbb sbn sbs sbt sbu sna snb snn sns snt snu ss- ssa ssb ssn sss sst ssu sta stb stn sts stt stu sua sub sun sus sut suu taa tab tan tas tat tau tba tbb tbn tbs tbt tbu tna tnb tnn tns tnt tsa tsb tsn tss tst tsu tta ttb ttn tts ttt ttu tua tub tun tus tut tuu ua- uaa uab uan uas uat uau uba ubb ubn ubs ubt ubu un- una unb unn uns unt unu usa usb usn uss ust usu uta utb utn uts utt utu uua uun uus uut uuu