Theoretical and observed light curves fitted by the W-D program. The solid lines (red) in the upper part are the theoretical light curves; the circles are the actual observed light curves from sky surveys. The light curves in the BV bands for HL Aur are from R.-X. Zhang et al. (1994); for UU Lyn, its light curves in the BV bands are from A. Yamasaki et al. (1983), and the R-band data are from L.-Y. Zhu et al. (2007). The fitting residuals are plotted in the bottom panel.