This is the 2451st most frequent Chinese word.
年輕
Young.
In this sentence, '年輕' describes the student's age and youthful characteristic.
這位學生非常年輕，但他的思維很成熟。
This student is very young, but his thoughts are mature.
Here, '年輕' characterizes the distinctive lifestyle of youth.
她過著年輕人特有的快樂生活。
She lives a joyful life that is typical for young people.
In this case, '年輕' metaphorically signifies the vigor commonly associated with youth.