  The effects of ground-state correlations on the dipole and quadrupole
excitations are studied for $^{40}$Ca and $^{48}$Ca using the extended random
phase approximation (ERPA) derived from the time-dependent density-matrix
theory. Large effects of the ground-state correlations are found in the
fragmentation of the giant quadrupole resonance in $^{40}$Ca and in the
low-lying dipole strength in $^{48}$Ca. It is discussed that the former is due
to a mixing of different configurations in the ground state and the latter is
from the partial occupation of the neutron single-particle states. The dipole
and quadrupole strength distributions below 10 MeV calculated in ERPA are in
qualitatively agreement with experiment.
