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Chop - fore-knuckle strike Often used in a fashion similar to a jab in western boxing, the chop choi is frequently used to force open different gates (targets) on the opponent to be struck by follow-up techniques. There are two main variations of this element, the yerng (yang) chop and the yum (yin) chop. The yerng chop originates from the hip and is executed at a slightly upward path and angle into the opponent's solar plexus and ribs. The yum chop is mostly executed towards the same targets, however the yum chop is executed from the ear-level of the practitioner with a drilling (twisting) motion that travels in a downward path and angle. The two variations are often used in conjunction with each other to continuously strike at the same target.