Think of the arms as the gate with two doors in oblique order that protects the body. Initiate an attack by threaten the eyes with you right by going through the front right door on his side, his will have to response with his left, lest he would lose his eyes. Meanwhile, your left should be maintaining contact with his right.
Should he push your right from outside towards inside, you should follow and make use of his forces to cut towards the inner joint of his right with the blade of your right arm, bending his arm and twisting his body with one coup; thus, opening up his right for further attack. This is the technique of the Felling Gate. This is particularly effective if the opponent uses force and holds your right, as his attention will be focused there and won’t be able to respond to your flow.
If the opponents pushes away your initiate attack from inside to outside, your right can then follow this movement and cuts toward the inner joint of his right with the inward facing side of your arm, twisting his arm with a pull motion, and gain control of his body. This is the technique of the Reverse Gate (反關手).
If the motion is performed on the outside of the opponent’s arms, then it is called Cradle Hold (摟手)