-er c-- ccc cce ccm ccp ccr cct ccx ce- cec cee cem cep cer cet cex cmc cme cmm cmp cmr cmt cmx cpc cpe cpm cpp cpr cpt cpx crc cre crm crp crr crt crx ctc cte ctm ctp ctr ctt ctx cxc cxp cxr cxt cxx ec- ecc ece ecm ecr ect ecx eec eee eem eep eer eet eex em- emc eme emm emp emr emt emx ep- epc epe epm epp epr ept epx erc ere erm erp err ert etc ete etm etp etr ett etx ex- exc exe exp exr ext exx m-r mc- mcc mce mcm mcp mcr mct mcx mec mee mem mep mer met mex mmc mme mmm mmp mmr mmt mmx mpc mpe mpm mpp mpr mpt mpx mrc mre mrm mrp mrr mrt mrx mtc mte mtm mtp mtr mtt mtx mxc mxp mxr p-p pcc pce pcm pcp pcr pct pcx pec pee pem pep per pet pex pmc pme pmm pmp pmr pmt pmx ppc ppe ppm ppp ppr ppt ppx prc pre prm prp prr prt prx pt- ptc pte ptm ptp ptr ptt ptx pxc pxe pxm pxr pxt rcc rce rcm rcp rcr rct rcx re- rec ree rem rep rer ret rex rmc rme rmm rmp rmr rmt rmx rpc rpe rpm rpp rpr rpt rpx rrc rrm rrp rrr rrt rtc rte rtm rtp rtr rtt rtx rxp rxr t-x tcc tce tcm tcp tcr tct tcx te- tec tee tem tep ter tet tex tmc tme tmm tmp tmr tmt tmx tpc tpe tpm tpp tpr tpt tpx trc tre trm trp trr trt trx ttc tte ttm ttp ttr ttt ttx txe txt xcp xcr xcx xee xem xep xer xet xex xmc xmm xmp xmr xmt xmx xpc xpe xpm xpp xpt xrc xrt xrx xtc xtm xtp xtr xtx xxp xxx