a receding chin的用法和样例：
- He has a receding chin [hairline].
他的下颚 [额头的发际] 向后缩 [削] 。
- And then his face was smooth, with a receding jaw.
- I remember Mr. Smith only for his receding chin and prominent spectacles.
- Tom has a receding hairline, ie His hair has stopped growing at the forehead and temples.