a.

1. 基础的；根本的，十分重要的[（+to）]
   The fundamental cause of his success is his hard work.

   他成功的根本原因是他工作努力。

2. 原始的；主要的[（+to）]
3. 【音】基音的，原音的

n.

1. 基本原则（或原理），根本法则（或规律）；纲要[P][（+of）]
   In three days, she had learned the fundamentals of cooking.

   三天之内她就学会了烹调的基本知识。

adj.

n.

1. a central or primary rule or principle.
2. Music  a fundamental note, tone, or frequency.