  The Newman-Penrose formalism is used to deal with the massless scalar,
neutrino, electromagnetic, gravitino and gravitational quasinormal modes (QNMs)
in Schwarzschild black holes in a united form. The quasinormal mode frequencies
evaluated by using the 3rd-order WKB potential approximation show that the
boson perturbations and the fermion perturbations behave in a contrary way for
the variation of the oscillation frequencies with spin, while this is no longer
true for the damping's, which variate with $s$ in a same way both for boson and
fermion perturbations.
