  Three topics about the application of quenched chiral perturbation theory to
matter fields are studied. It is proved that the hairpin axial current
couplings in quenched chiral perturbation theories do not contribute to the
quenched chiral singularities for one chiral loop renormalization of matter
field properties. The modification of mass corrections in the chiral limit due
to nonzero mass splittings are studied, and selection rules for hadron decays
in quenched QCD are obtained.
