Upper arm is about equal in length to the shoulder blade in order to allow for good extension.

上臂长度约等于肩胛骨，以便为良好的扩展性。

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Upper arm and scapula are approximately equal in length and form an angle of 90 degrees.

上臂骨与肩胛骨长度基本一致，并呈90度角。

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Length of shoulder blade and upper arm are equal. Height from elbow to Withers approximately equals height from ground to elbow.

肩胛骨与上臂长度相等，从肘部到马肩隆与从地面到肘部的长度相等。

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