  Special features of magnetohydrodynamic waves linear dynamics in smooth shear
flows are studied. Quantitative asymptotic and numerical analysis are performed
for wide range of system parameters when basic flow has constant shear of
velocity and uniform magnetic field is parallel to the basic flow. The special
features consist of magnetohydrodynamic wave mutual transformation and
over-reflection phenomena. The transformation takes place for arbitrary shear
rates and involves all magnetohydrodynamic wave modes. While the
over-reflection occurs only for slow magnetosonic and Alfv\'en waves at high
shear rates. Studied phenomena should be decisive in the elaboration of the
self-sustaining model of magnetohydrodynamic turbulence in the shear flows.
