  We examine the dynamics of a neutral particle around a Kerr-Newman black
hole, and in particular focus on the effects of the charge of the spinning
black hole on the motion of the particle. We first consider the innermost
stable circular orbits (ISCO) on the equatorial plane. It is found that the
presence of the charge of the black hole leads to the effective potential of
the particle with stronger repulsive effects as compared with the Kerr black
hole. As a result, the radius of ISCO decreases as charge $Q$ of the black hole
increases for a fixed value of black hole's angular momentum $a$. We then
consider a kick on the particle from its initial orbit out of the equatorial
motion. The perturbed motion of the particle will eventually be bounded, or
unbounded so that it escapes to spatial infinity. Even more, the particle will
likely be captured by the black hole. Thus we analytically and numerically
determine the parameter regions of the corresponding motions, in terms of the
initial radius of the orbital motion and the strength of the kick. The
comparison will be made with the motion of a neutral particle in the Kerr black
hole.
