求翻译：双脚分开与肩同宽，膝关节慢慢做下蹲动作，保持上身直立，大腿最好与地面平行，两只胳膊向前平举，保持15秒，这个动作有助于预防脊椎疾病。是什么意思？

Feet apart at shoulder width, knee slowly do a squat action, keeping the upper body upright, thigh preferably parallel to the ground, his arms held flat forward, hold for 15 seconds, this action will help prevent spinal diseases.

With your feet shoulder-width apart, knees and squat down so slowly, keep your upper body upright, the thighs parallel to the ground, it would be better with his arms holding FORWARD, hold for 15 seconds, this move helps to prevent spinal cord disease.

The both feet separates with the shoulder same width, the knee joint does slowly squats the movement, maintains the upper body erectness, the thigh is best with the ground parallel, two arms evenly lift forward, maintain for 15 seconds, this movement is helpful to the prevention vertebra disease.

Separated from feet and shoulder width, knees slowly to do squat action, keep the upper body upright, best thighs parallel to the ground, two arm Xiang Qianping for 15 seconds, this action will help prevent spinal disease.