A. The rear point plate force direction is incorrect easy to lead to fall board!
B. The forefoot ankle joint is too stiff, not to be able to relax the ankle joint with the instep to stick the board head easily makes the board head deviate!
C. Front lift plate head when looking at the side easily lead to pull plate deviation and falling plate, Ollie Head should try to keep in the center of gravity and the direction of the Board of the operation of the plane and maintain the face front, look at the feet as far as possible with the peripheral!
D. forefoot feet too fast, afraid of falling, easy to make the front foot out of the board!