-er a-a a-c aaa aac aae aar aas aav ac- aca acc ace acr acs acv aea aec aee aer aes aev ar- ara arc are arr ars arv as- asa asc ase asr ass asv av- ava avc ave avr avs c-- caa cac cae car cas cav cca ccc cce ccr ccs ccv ce- cea cec cee cer ces cev cra crc cre crr crs crv csa csc cse csr css csv cva cvc cve cvr cvs cvv eaa eac eae ear eas eav ec- eca ecc ece ecr ecs ecv eea eec eee eer ees eev era erc ere err ers erv es- esa esc ese esr ess esv eva evc eve evr evs evv ra- raa rac rae rar ras rav rca rcc rce rcr rcs rcv re- rea rec ree rer res rev rra rrc rrr rrs rsa rsc rse rsr rss rsv rva rvc rve rvr rvs rvv saa sac sae sar sas sav sca scc sce scr scs scv se- sea sec see ser ses sev sr- sra src sre srr srs srv ss- ssa ssc sse ssr sss ssv sva svc sve svr svs svv v-a v-e vaa vac vae var vas vav vca vcc vce vcr vcs vea vec vee ver ves vra vrc vre vrr vrs vsa vsc vse vsr vss vsv vva vvc vvr vvs vvv