rei rek rel reo rep rer res ret ria ric rie rii rik ril rio rip rir ris rit rkc rke rkk rko rkp rks rkt rla rlc rle rli rll rlo rlp rlr rls rlt roa roc roe roi rok rol roo rop ror ros rot rpa rpc rpe rpi rpk rpl rpo rpp rpr rps rpt rra rrc rri rrk rrl rrp rrr rrs rrt rsa rsc rse rsi rsk rsl rso rsp rsr rss rst rta rtc rte rti rtk rtl rto rtp rtr rts rtt saa sac sae sai sak sal sao sap sar sas sat sca scc sce sci sck scl sco scp scr scs sct se- sea sec see sei sek sel seo sep ser ses set sia sic sie sii sik sil sio sip sir sis sit sk- ska skc ske ski skk skl sko skp skr sks skt sla slc sle sli slk sll slo slp slr sls slt soa soc soe soi sok sol soo sop sor sos sot spa spc spe spi spk spl spo spp spr sps spt sr- sra src sre sri srk srl sro srp srr srs srt ss- ssa ssc sse ssi ssk ssl sso ssp ssr sss sst sta stc ste sti stk stl sto stp str sts stt taa tac tae tai tak tal tao tap tar tas tat tca tcc tce tci tck tcl tco tcp tcr tcs tct te- tea tec tee tei tek tel teo tep ter tes tet tia tic tie tii tik til tio tip tir tis tit tka tkc tke tkk tkl tko tkp tkr tks tkt tla tlc tle tli tlk tll tlo tlp tlr tls tlt to- toa toc toe toi tok tol too top tor tos tot tpa tpc tpe tpi tpk tpl tpo tpp tpr tps tpt tra trc tre tri trk trl tro trp trr trs trt tsa tsc tse tsi tsk tsl tso tsp tsr tss tst tta ttc tte tti ttk ttl tto ttp ttr tts ttt