fere[8], free[8], geek[7], gder[7], grek[7], kred[6], erek[5],
fee[7], ref[7], keg[6], dek[5], erg[5], der[4], red[4], ker[4], rek[4],
ef[6], fe[6], de[3], ee[2], er[2], re[2],
