When people sleep on their front, their lower jaw is positioned further forward than normal.

因为当人们俯卧的时候，下颚会比平时更加突出。

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Main products are: Continental C Series jaw crusher machine and its components, a moving jaw, front plate, back plate, dental plates, side guard, jaw plate, eccentric shaft, flywheel, bearing, etc.

主营产品有：欧式C系列颚式破碎机整机及其部件，有动颚、前板、后板、牙板、边护板、颚板、偏心轴、 飞轮、 轴承座等；

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Moreover, the bones in the front part of a baleen whale's lower jaw, or mandible, aren't fused as they are in other mammals.

另外，须鲸下颚前部的骨骼，也就是所说的下颌骨，并不像其他哺乳动物一样是愈合在一起的。

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Typically, this involves one jab in front of each ear and another at the angle of the jaw on each side of the face.

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