When you sleep on your back, your tongue falls backwards into your throat which can narrow your airway and partly block airflow.

仰睡会让舌头滑落到咽喉部位，减小了呼吸道的面积，一定程度上阻塞了空气流通。

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Little to no front-to -back (longitudinal) airflow takes place.

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Mercedes will wait until Bahrain to introduce their definitive aerodynamic package - which will include a modified diffuser, a crucial part that defines airflow at the back of the car and has a huge role in producing downforce.

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