Before learning to use english, it is extremely important to understand the tangent line. The tangent line tells us where the CB is going to travel if we don't use any english, draw, or follow. Once we understand where the CB will go without any spin, then we can use spin to alter that path. We can use the tangent line as a reference to determine the natural path, and then use our knowledge of spin to change that path.
Follow and draw will alter the path of the CB after it contacts the OB. Follow will cause the CB to roll forward of the tangent line, draw will cause the CB to come back from the tangent line (see diagram 2).
Line C is the path of the CB when using follow. Line D is the path of the CB when using draw. Notice that the CB follows the tangent line before rolling forward or coming back. This path is actually a parabola. Once the CB contacts the OB, it follows the tangent line until friction grabs the ball and the spin causes it to move forward (follow) or backward (draw). If the CB is struck harder, it stays on the tangent line longer. If we use follow and strike the CB hard, it would follow this line (see diagram 3).
