  In this paper, a quadratic system with two parallel straight line-isoclines
is considered. This system corresponds to the system of class II in the
classification of Ye Yanqian. Using the field rotation parameters of the
constructed canonical system and geometric properties of the spirals filling
the interior and exterior domains of its limit cycles, we prove that the
maximum number of limit cycles in a quadratic system with two parallel straight
line-isoclines and two finite singular points is equal to two. Besides, we
obtain the same result in a different way: applying the Wintner-Perko
termination principle for multiple limit cycles and using the methods of global
bifurcation theory developed earlier by the author.
