simple

adjective [原级]简单的，简明的；简朴的，朴素的；纯粹的，完全的；结构单一的，简易的；普通的，平凡的；愚笨的，迟钝的；（动词时态）简单的；（数）简单的；（叶、茎）没有分杈的；（镜头、显微镜等）单镜头的；（利息）单利的；（句子）无从句的

If you describe people or things as simple, you mean that they have all the basic or necessary things they require, but nothing extra. ^{简朴的; 朴素的}