  The quark potential model is extended to include the sea quark excitation
using the random phase approximation (RPA). The effective quark interaction
preserves the important Quantum Chromodynamics (QCD) properties -- chiral
symmetry and confinement simultaneously. A primary qualitive analysis shows
that the $\pi$ meson as a well-known typical Goldstone boson and the other
mesons made up of valence $q\bar{q}$ quark pair such as the $\rho$ meson can
also be described in this extended quark potential model.
