  We calculate single pion production by neutrinos in the resonance region. We
consider both charged and neutral current reactions on free protons and
neutrons. We present differential and total cross sections which can be
compared with experiments. Then we use these results to calculate the spectra
of the emerging pions including the Pauli suppression factor and rescattering
corrections for reactions in heavy nuclei. Our results will be useful for
studying single pion production and for investigating neutrino oscillations in
future experiments.
