We consider the properties of two-dimensional drift-oscillatory motion of a
relativistic charged particle under the action of harmonic driving electric force. It
is shown that the longitudinal and transverse drift speeds are not equal
to the corresponding initial components of the speed and depend on the
initial conditions. Under certain conditions, the dependence of the transverse
component of the drift velocity on the amplitude of the external force (or
the inverse frequency) has an intermediate maximum. We also discuss the
circumstances under which the localization of the particle or reversing of its
initial longitudinal motion, as well as the oscillation attenuation effect take
place.
