When the zygomaticusmajor muscles in our cheeks contract, they draw up the corners of our mouths.
当我们面颊两侧颧肌收缩时,嘴角就会提起。
2
We think of them as signifying happiness, and indeed, researchers do find that the more intensely people contract their zygomaticusmajor muscles, the happier they say they feel.