And inference center detects when his cheek muscle moves up.

感应中心可以监测到他面部肌肉的提拉动作。

He thought so hard his cheek muscles made little knots under his grayish skin.

他苦思冥想， 脸颊上的肌肉在他灰白的皮肤下起了一个个小疙瘩。