Example of the evolution of a binary. The solid line, dashed line, and dash-dot line represent the mass of the WD (M_WD), the mass of the companion star (M₂), and the mass transfer rate between the binary (ṁ), respectively. The initial mass of the WD is 1.25 M_⊙, and the mass of the companion star is 2.0 M_⊙. The initial binary orbital period is 1.7 d. Here, the Ṁ_st represents the stable accretion rate onto the WD.