  Among the most important tasks of neutrino oscillation experiments is
correctly estimating the parent neutrino energy from the by-products of their
interactions. Large uncertainties in our current understanding of such
processes can significantly hamper this effort. We explore several recent
measurements made using the \mnv{} detector in the few-GeV NuMI muon neutrino
beam at Fermilab: the differential cross-section vs. $Q^2$ for charged-current
quasi-elastic scattering, the differential cross-sections vs. pion angle and
pion kinetic energy for resonant single charged pion production, and the
differential cross-sections vs. pion angle and kinetic energy for coherent pion
production. We furthermore discuss their implications for energy reconstruction
in oscillation measurements.
