How to create good light and shade

What exactly does the word "light and shade" mean?
Faced with this problem, many people may have learned some art. Who doesn't know the "light and dark" part, is not the bright part and the dark part? This is too narrow, and it is only the thinking mode of plane media, which has great limitations. As a modern society, art and design must use the concept of expansion to understand the so-called "light and shade".
“明暗”这个词到底是什么意思？
面对这个问题，很多人可能学过一些美术。“明暗”谁不知道，不就是亮部和暗部嘛？这个话太狭隘，而且只是平面媒介的思维方式，有很大的局限性。作为一个现代社会的美术和设计一定要用拓展的概念去理解所谓的“明暗”。