欢迎学习素描基础知识。今天我们将探讨三大面和五大调，这些是创造具有真实光影效果素描作品的基本概念。这些原理帮助艺术家理解光线如何与三维形体相互作用。
The three major planes form the foundation of understanding form in light. The light plane receives direct illumination and appears brightest. The gray plane is the transitional area between light and shadow. The dark plane is in shadow and appears darkest. These three planes help artists organize the major value relationships in their drawings.