pein[7], peri[7], pier[7], prei[7], iren[4], rein[4], irre[4],
pin[6], per[6], rep[6], ein[3], nie[3], ire[3], ern[3], ren[3], irr[3],
pi[5], ei[2], ne[2], in[2], er[2], re[2],
