indispensable，英语单词，主要用作形容词，名词，形容词意思是“不可缺少的；绝对必要的；
责无旁贷的”，名词意思是“不可缺少之物；必不可少的人”。
Sound should enhance your site but not be indispensable.
Ah! Red is the color of life, indispensable. I like red.
To be without some of the things you want is an indispensable part of happiness.