\begin{table}%t4 \caption{\label{tab4}Birth rates of hot subdwarfs from the stable RLOF channel of intermediate-mass binaries (our model) and other channels (Han et~al. \cite{Han03}) (in 10$^{-3}$~yr$^{-1}$).} %%\centerline {\small \begin{tabular}{lccccccc} \hline \hline $Z$ & $q_{\rm crit}$ & $\nu_{\rm IMR}$ & $\nu_{\rm FR}$ & $\nu_{\rm FCE}$ & $\nu_{\rm SR}$ & $\nu_{\rm SCE}$ & $\nu_{\rm M}$\\ \hline 0.02 & 1.5 & 4.18 & 29.89& 8.41 &0.00&8.38&17.22\\ 0.02 & 1.2 & 4.14 & 22.25 &10.71 &0.00&5.43&7.99\\ \hline \end{tabular}} \par \medskip $Z$ = metallicity; $q_{\rm crit}$ = the critical mass ratio for the first stable RLOF on the FGB; $\nu_{\rm IMR}$ = Galactic birth rates of hot subdwarfs from the stable RLOF channel of intermediate-mass binaries; $\nu_{\rm FR}$ = the first stable RLOF channel; $\nu_{\rm FCE}$ = the first CE ejection channel; $\nu_{\rm SR}$ = the second RLOF channel; $\nu_{\rm SCE}$ = the second CE ejection channel; $\nu_{\rm M}$ = the helium WD merger channel. \end{table}