学生

In a sentence

• 我是一个学生。

  I am a student.

  Here, '学生' is a noun used to identify the speaker's role or identity.

• 他是一个好学生。

  He is a good student.

  In this sentence, '学生' is a noun modified by the adjective '好' to describe the quality of the person.

• 你在学校看到很多学生。

  You see many students at the school.

  Here, '学生' is used as a countable noun to indicate multiple individuals who learn at a school.