  We study physics on $\rho(770)$ and $\omega(782)$ in framework of chiral
constituent quark model. The effective action is derived by proper vertex
method, which can capture all order information of chiral expansion. The
$N_c^{-1}$ expansion is also studied systematically. It is shown that the
momentum expansion at vector meson energy scale converges slowly, and the loop
effects of pseudoscalar meson play an important role at this energy scale. We
provide a method to prove the unitarity of S-matrix in any low-energy effective
theory of QCD. Phenomenologically, we study decays for $\rho\to\pi\pi$,
$\rho\to e^+e^-$, $\omega\to\pi^+\pi^-$, $\rho^\pm\to\gamma\pi^\pm$ and
$\omega\to\gamma\pi^0$, $\rho^0-\omega$ mixing and their mass splitting, pion
form factor, $I=l=1$ phase shift and light quark masses at vector meson energy
scale. These results include all order contribution of vector meson momentum
expansion and is up to next to leading order of $N_c^{-1}$ expansion. All of
these theoretical predictions agree with data very well. The unitarity of
S-matrix yielded by this framework is examined. The Breit-Winger formula for
resonance propagator is derived.
