obu[7], bru[7], bur[7], ber[5], erb[5], reb[5], bor[5], rob[5], oru[5], web[5], ero[3], ewo[3], owe[3], rew[3], wre[3], rwo[3],
bu[6], be[4], bo[4], wu[4], eo[2], er[2], re[2], or[2], ro[2], ew[2], we[2],