  The doping and energy evolution of the magnetic excitations of the
electron-doped cuprate superconductor Pr$_{0.88}$LaCe$_{0.12}$CuO$_{4-\delta}$
in the superconducting state is studied based on the kinetic energy driven
superconducting mechanism. It is shown that there is a broad commensurate
scattering peak at low energy, then the resonance energy is located among this
low energy commensurate scattering range. This low energy commensurate
scattering disperses outward into a continuous ring-like incommensurate
scattering at high energy. The theory also predicts a dome shaped doping
dependent resonance energy.
