The $B(B_s)\to D_{(s)}P$, $D_{(s)}V$, $D_{(s)}^{\ast }P$ and $D_{(s)}^{\ast }V$ decays in the perturbative QCD approach

Two-body non-leptonic charmed decays $B_{(s)}\to D_{(s)}P$, $D_{(s)}^{\ast }P$, $D_{(s)}V$ and $D_{(s)}^{\ast }V$ are analyzed in perturbative QCD approach, where $P$ and $V$ denote the light pseudoscalar meson and vector meson, respectively. We test the $D$ meson wave function by a ${\chi }^2$ fit with experimental data of six $B\to DP$ channels. We give the branching ratios of all the charmed B decay channels, most of which agree with experiments amazingly well. The predicted $B_s$ decays can be confronted with the future experimental data. By straightforward calculations, our pQCD approach gives the right relative strong phase of $a_2\mathrm{/}{a}_1$ with experiments. We also predict the percentage of transverse polarizations in $B_{(s)}\to D^{\ast }V$ decay channels.