  We construct an effective Lagrangian of heavy and light mesons with $1/M_Q$
correction. The Lagrangian is constructed model independent way by using only
the information of the symmetry of QCD. Reparameterisation invariance at the
meson level is taken into account for the consistency of the theory. The
partial decay width of the process $D^{*+} \rightarrow D^0 \pi^+$ and the form
factors of the process ${\bar B}^0 \rightarrow \pi^+ l {\bar \nu}$ are
calculated with the $1/M_Q$ correction. We also introduce the light vector
mesons based on the approach of the hidden local symmetry. The form factors of
the process ${\bar B}^0 \rightarrow \rho^+ l {\bar \nu}$ are calculated with
thus introduced $\rho$-meson. These results are easily translated to the
$D$-meson semileptonic decays.
