It is crucial that the upper back and neck are held in an erect position to give support for the head.

重要的是：上背和颈部要挺直以支撑头部，这一点很重要。

《柯林斯英汉双解大词典》

To lose an upright or erect position suddenly.

突然失去垂直的或笔直的位置。

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Dorsal position was adopted in the first group and hugged-erect position in the second group.

第一组均采用仰卧位透视，第二组均采用抱立位透视。

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An erect posture may be a sign of a tough bargaining position or it may simply indicate a stiff back.

FORBES: How Savvy Negotiators Read Your Body Language