-er a-a aaa aae aar aav aax aea aee aer aev aex ar- ara are arr arv arx av- ava ave avr avx ax- axa axe axr axv axx eaa eae ear eav eax eea eee eer eev eex era ere err erv eva eve evr evv ex- exa exe exr exx ra- raa rae rar rav rax re- rea ree rer rev rex rra rrr rva rve rvr rvv rxr v-a v-e vaa vae var vav vax vea vee ver vex vra vre vrr vva vvr vvv vxa vxr vxv xaa xar xav xee xer xev xex xrx xxv xxx