Quick string change is fast because of the high speed. If the string is changed with the active movement of the middle and ring fingers, the fingers will be overburdened and cannot last for a long time. Not easy to be even. Therefore, the finger movements of fast string changing are actually driven by other parts of the right hand. There are two kinds of fast string changing: forward and reverse, and they have certain differences in action.

Pull the inner string first and then push the outer string to change the string in the forward direction. In the forward string change, the movement of the fingers is driven by the wrist... Pulling the outer string first and then pushing the inner string is called reverse string changing. In reverse string change, the action of changing the bow is driven by the arm...In reverse string change, the middle finger and ring finger can be said to have no movement at all, and the bow moves as a whole under the back and forth swing of the arm... When playing the bow Circles, too,—… The way of movement is very similar to the action of grinding ink before writing with a brush.