under age

例句：

1. 1.The child was under age for the job.
   这个孩子不适合这份工作。
2. 2. She is under age and cannot drive.
   她未成年，不能开车。
3. 3.Under age students often face more challenges than their older peers.
   未成年学生往往比他们的同龄人面临更多的挑战。