Key idea
Compare a bent-leg spring with Harai-goshi’s sweeping leg.
For right , draws forward and turns the right hip into close contact. Tori’s bent right leg connects along the inside of Uke’s right leg. The hip and bent leg spring upward together as the hands turn Uke forward; mirror on the left. Compare , whose leg sweeps rather than forming the same bent-leg spring. Keep the contact broad rather than driving the knee into Uke.