\begin{table}%t3 \caption{\label{tab3}Parameters of some typical hot subdwarfs and their progenitors.} %%\centerline {\small \begin{tabular}{lcccc} \hline \hline $M_{\rm 1i}$ / $M_{\rm f}($\rm type$)$ & $q_{\rm i}$ & $P_{\rm i}$ / $P_{\rm f}$ & $M_{\rm env}$ & $t_{\rm age}$ \\ ($M_{\odot}$) & & (days) & ($M_{\odot}$) & (yrs) \\ \hline conservative case: \\ 3.55/0.38(sdB) & 1.1 & 1.5/151.1 & 0.02 & $3.8\times 10^{8}$\\ 3.55/0.56(sdB) & 1.1 & 3.5/116.1 & 0.04 & $0.9\times 10^{8}$\\ 3.55/0.53(sdB) & 4.0 & 3.5/11.5 & 0.04 & $1.1\times 10^{8}$\\ 5.01/0.54(sdB) & 1.1 & 1.6/147.8 & 0.04 & $1.0\times 10^{8}$\\ 5.01/0.65(sdOB) & 1.1 & 2.5/137.3 & 0.05 & $0.6\times 10^{8}$\\ 5.01/0.93(sdO) & 1.1 & 15.7/317.2 & 0.09 & $0.2\times 10^{8}$\\ 5.01/1.01(sdOB) & 1.1 & 31.3/483.8 & 0.12 & $0.2\times 10^{8}$\\ 5.01/1.06(sdB) & 1.1 & 40.6/545.5 & 0.16 & $0.1\times 10^{8}$\\ 5.01/0.84(sdO) & 4.0 & 5.1/13.1 & 0.08 & $0.2\times 10^{8}$\\ 5.01/0.91(sdO) & 4.0 & 32.3/60.8 & 0.09 & $0.2\times 10^{8}$\\ \hline non-conservative case: \\ 3.55/0.33(sdB) & 1.1 & 1.5/27.9 & 0.01 & $7.9\times 10^{8}$\\ 3.55/0.54(sdB) & 1.1 & 3.5/29.4 & 0.04 & $1.0\times 10^{8}$\\ 3.55/0.53(sdB) & 4.0 & 3.5/6.9 & 0.04 & $1.1\times 10^{8}$\\ 5.01/0.46(sdB) & 1.1 & 1.6/27.2 & 0.03 & $1.7\times 10^{8}$\\ 5.01/0.61(sdOB) & 1.1 & 2.5/29.0 & 0.05 & $0.7\times 10^{8}$\\ 5.01/0.91(sdO) & 1.1 & 15.7/100.5 & 0.09 & $0.2\times 10^{8}$\\ 5.01/0.98(sdOB) & 1.1 & 41.6/483.2 & 0.12 & $0.2\times 10^{8}$\\ 5.01/1.00(sdB) & 1.1 & 43.6/526.0 & 0.14 & $0.1\times 10^{8}$\\ 5.01/0.84(sdO) & 4.0 & 5.1/9.1 & 0.08 & $0.3\times 10^{8}$\\ 5.01/0.91(sdO) & 4.0 & 32.3/59.4 & 0.09 & $0.2\times 10^{8}$\\ \hline \end{tabular}} \medskip \par $M_{\rm 1i} =$ initial mass; $M_{\rm f} =$ the mass of hot subdwarfs; $q_{\rm i} =$ the mass ratio; $P_{\rm i} =$ initial orbital period; $P_{\rm f} =$ orbital period of hot subdwarf binaries; $M_{\rm env} =$ the envelope mass of hot subdwarfs; $t_{\rm age} =$ the lifetime of a hot subdwarf. More parameters can be seen from Figs.~\ref{fig2}, \ref{fig3}, and 6--9. \end{table}