sdt sdu se- seb sec sed see sef sem sen seo ses set seu sfb sfc sfd sfe sff sfm sfn sfo sfs sft sfu smb smc smd sme smf smm smn smo sms smt smu snb snc snd sne snf snm snn sno sns snt snu sob soc sod soe sof som son soo sos sot sou ss- ssb ssc ssd sse ssf ssm ssn sso sss sst ssu stb stc std ste stf stm stn sto sts stt stu sub suc sud sue suf sum sun suo sus sut suu tbb tbc tbd tbe tbf tbm tbn tbo tbs tbt tbu tcb tcc tcd tce tcf tcm tcn tco tcs tct tcu tdb tdc tdd tde tdf tdm tdn tdo tds tdt tdu te- teb tec ted tee tef tem ten teo tes tet teu tfb tfc tfd tfe tff tfm tfn tfo tfs tft tfu tmb tmc tmd tme tmf tmm tmn tmo tms tmt tmu tnb tnc tnd tne tnf tnm tnn tno tns tnt to- tob toc tod toe tof tom ton too tos tot tou tsb tsc tsd tse tsf tsm tsn tso tss tst tsu ttb ttc ttd tte ttf ttm ttn tto tts ttt ttu tub tuc tud tue tuf tum tun tuo tus tut tuu ubb ubc ube ubf ubn ubo ubs ubt ubu ucb ucc ucd uce ucf ucm ucn uco ucs uct ucu udb udc udd ude udf udm udn udo uds udt udu ueb uec ued uee uef uem uen ues uet ufc ufd ufe uff ufm ufn ufo ufs uft ufu um- umb umc umd ume umf umm umn umo ums umt umu un- unb unc und une unf unm unn uno uns unt unu uob uoc uod uoe uom uon uoo uos uot usb usc usd use usf usm usn uso uss ust usu utb utc utd ute utf utm utn uto uts utt utu uuc uue uum uun uus uut uuu