-er a-a a-b a-q aaa aab aae aaq aar ab- aba abb abe abq abr aea aeb aee aeq aer aqa aqr ar- ara arb are arq arr baa bab bae baq bar bba bbb bbe bbq bbr be- bea beb bee beq ber bqe bra brb bre brq brr eaa eab eae ear eba ebb ebe ebq ebr eea eeb eee eer eqa eqe eqq era erb ere erq err qaa qar qba qbe qbq qee qqq qra qrb qre ra- raa rab rae raq rar rba rbb rbe rbr re- rea reb ree req rer rra rrb rrq rrr