spi spl spn spo spp spr sps spt spx sr- src sre sri srl srn sro srp srr srs srt srx ss- ssc sse ssi ssl ssn sso ssp ssr sss sst ssx stc ste sti stl stn sto stp str sts stt stx sxc sxi sxl sxn sxs sxt t-x tcc tce tci tcl tcn tco tcp tcr tcs tct tcx te- tec tee tei tel ten teo tep ter tes tet tex tic tie tii til tin tio tip tir tis tit tix tlc tle tli tll tln tlo tlp tlr tls tlt tlx tnc tne tni tnl tnn tno tnp tnr tns tnt tnx to- toc toe toi tol ton too top tor tos tot tox tpc tpe tpi tpl tpn tpo tpp tpr tps tpt tpx trc tre tri trl trn tro trp trr trs trt trx tsc tse tsi tsl tsn tso tsp tsr tss tst tsx ttc tte tti ttl ttn tto ttp ttr tts ttt ttx txe txi txl txn txs txt xci xcl xcp xcr xcx xee xel xen xep xer xes xet xex xic xie xii xin xio xis xit xix xli xlr xls xlt xnc xno xns xoc xoi xon xoo xop xor xos xot xox xpc xpe xpl xpn xpo xpp xps xpt xrc xrt xrx xsc xsi xsl xsp xss xst xtc xti xtp xtr xts xtx xxi xxl xxo xxp xxx