betce[9],
bece[7], obce[7], obco[7], beto[7], boot[7], tece[6], ocet[6],
cob[6], bet[6], bot[6], bee[5], eto[4], oto[4],
be[4], bo[4], ce[3], co[3], et[3], te[3], ot[3], to[3], ee[2], eo[2],
