reff[10], riff[10], fier[7], frei[7], reif[7], rief[7], freu[7], rufe[7], ufer[7], ufre[7],
uff[9], fei[6], ruf[6], ire[3], reu[3], ure[3],
ei[2], er[2], re[2], ui[2], ur[2],
