plc pld ple plf plg pli plk pll plp pls plt ppc ppd ppe ppf ppg ppi ppk ppl ppp pps ppt ps- psc psd pse psf psg psi psk psl psp pss pst pt- ptc ptd pte ptf ptg pti ptk ptl ptp pts ptt scc scd sce scf scg sci sck scl scp scs sct sdc sdd sde sdf sdg sdi sdk sdl sdp sds sdt se- sec sed see sef seg sei sek sel sep ses set sfc sfd sfe sff sfg sfi sfk sfl sfp sfs sft sgc sgd sge sgf sgg sgi sgk sgl sgp sgs sgt sic sid sie sif sig sii sik sil sip sis sit sk- skc skd ske skf skg ski skk skl skp sks skt slc sld sle slf slg sli slk sll slp sls slt spc spd spe spf spg spi spk spl spp sps spt ss- ssc ssd sse ssf ssg ssi ssk ssl ssp sss sst stc std ste stf stg sti stk stl stp sts stt tcc tcd tce tcf tcg tci tck tcl tcp tcs tct tdc tdd tde tdf tdg tdi tdk tdl tdp tds tdt te- tec ted tee tef teg tei tek tel tep tes tet tfc tfd tfe tff tfg tfi tfk tfl tfp tfs tft tgc tge tgf tgg tgi tgk tgl tgp tgs tgt tic tid tie tif tig tii tik til tip tis tit tkc tke tkg tkk tkl tkp tks tkt tlc tld tle tlf tlg tli tlk tll tlp tls tlt tpc tpd tpe tpf tpg tpi tpk tpl tpp tps tpt tsc tsd tse tsf tsg tsi tsk tsl tsp tss tst ttc ttd tte ttf ttg tti ttk ttl ttp tts ttt