Keep your front shin vertical, back knee straight, back heel lifted, and chest lifted.

保持前面小腿垂直地板，后膝伸直，后脚跟离地，胸腔上展。

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If the chest is sticking out then the middle of the back will be flat allowing for the spinal cord to stack in a vertical line.

如果胸膛往外挺拔，背部的中段部位就会笔直，这样允许脊柱能形成一条垂直线。

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