英语语法分析

The zygomaticus minor and orbicularis oris secondarily provide lateral wall stability.

颧小肌和和口轮匝肌则辅助维持外侧壁稳定。

The zygomaticus minor and orbicularis oris secondarily provide lateral wall stability.

颧小肌和和口轮匝肌则辅助维持外侧壁稳定性。

And they mean it: they smile with their eyes (a contraction of the orbicularis oculi facial muscles), not just their mouths.

这意味着：他们用眼睛微笑(面部上睑提肌肌肉的收缩)，而不仅仅是他们的嘴。