-er -ic c-- ccc cce cci ccr ccs ccx ce- cec cee cei cer ces cex ci- cic cie cii cir cis cix crc cre cri crr crs crx csc cse csi csr css csx cxc cxi cxr cxs cxx ec- ecc ece eci ecr ecs ecx eec eee eer ees eex eic eie eii eir eis eix erc ere eri err ers es- esc ese esi esr ess esx ex- exc exe exi exr exs exx icc ice ici icr ics ie- iec iee iei ier ies iex iic iie iii iir iis iix ir- irc ire iri irr irs irx is- isc ise isi isr iss ixc ixe ixi rcc rce rci rcr rcs rcx re- rec ree rei rer res rex ric rie rii rir ris rix rrc rri rrr rrs rsc rse rsi rsr rss rsx rxr rxs scc sce sci scr scs scx se- sec see sei ser ses sex sic sie sii sir sis six sr- src sre sri srr srs srx ss- ssc sse ssi ssr sss ssx sxc sxi sxs xci xcr xcx xee xer xes xex xic xie xii xis xix xrc xrx xsc xsi xss xxi xxx