sr- srb src sre srf sri srm srn srr srs srt sry ss- ssb ssc sse ssf ssi ssm ssn ssr sss sst stb stc ste stf sti stm stn str sts stt sty sy- syb syc sye syi sym syn syr sys syt tbb tbc tbe tbf tbi tbm tbn tbr tbs tbt tcb tcc tce tcf tci tcm tcn tcr tcs tct te- teb tec tee tef tei tem ten ter tes tet tey tfb tfc tfe tff tfi tfm tfn tfr tfs tft tib tic tie tif tii tim tin tir tis tit tiy tmb tmc tme tmf tmi tmm tmn tmr tms tmt tmy tnb tnc tne tnf tni tnm tnn tnr tns tnt trb trc tre trf tri trm trn trr trs trt try tsb tsc tse tsf tsi tsm tsn tsr tss tst tsy ttb ttc tte ttf tti ttm ttn ttr tts ttt tty tyc tye tyf tym tyn tyr tys tyt ybc ybe ybf ybi ybm ybr ybs yby ycc yce ycf yci ycs ycy yeb yec yee yef yei yem yen yer yes yet yey yfc yfe yff yfm yfr yfs yft yie yif yii yim yin yir yis yit ymc yme ymi ymm yms ymt yne ynn yns yny yrc yre yrf yrn yrs yrt ysb ysc yse ysi ysm ysr yss yst ysy ytc yte ytf ytm ytn ytr yts ytt yyb yyc yye yyf yys yyt yyy