-th a-a a-b a-t aaa aab aah aao aas aat aax ab- aba abb abh abo abs abt abx aha ahb ahh aho ahs aht ahx aoa aob aoh aoo aos aot aox as- asa asb ash aso ass ast asx at- ata atb ath ato ats att atx ax- axa axh axo axs axt axx baa bab bah bao bas bat bax bba bbb bbh bbo bbs bbt bbx bha bhb bhh bho bhs bht bhx boa bob boh boo bos bot box bsa bsb bsh bso bss bst bsx bta btb bth bto bts btt btx bxb bxo bxx haa hab hah hao has hat hax hba hbb hbh hbo hbs hbt hbx hha hhb hhh hho hhs hht hoa hob hoh hoo hos hot hox hsa hsb hsh hss hst hsx hta htb hth hto hts htt htx oaa oab oah oao oas oat oax ob- oba obb obh obo obs obt obx oha ohh oho ohs oht oo- ooa oob ooh ooo oos oot oox os- osa osb osh oso oss ost osx ot- ota otb oth oto ots ott ox- oxa oxb oxo oxt oxx saa sab sah sao sas sat sax sba sbb sbh sbo sbs sbt sbx sh- sha shb shh sho shs sht soa sob soh soo sos sot sox ss- ssa ssb ssh sso sss sst ssx sta stb sth sto sts stt stx sxs sxt t-x taa tab tah tao tas tat tax tba tbb tbh tbo tbs tbt th- tha thb thh tho ths tht thx to- toa tob toh too tos tot tox tsa tsb tsh tso tss tst tsx tta ttb tth tto tts ttt ttx txs txt xaa xas xat xbx xht xoa xoo xos xot xox xsa xsb xss xst xts xtx xxo xxx