Okay, here is the translation following your instructions: Plaster Head Sculpture Chapter

Author: Shi Youpeng, Zheng Xumin
Publisher:
Publish Date: 2004-11-01
Features: First, the anatomical structure of the human head and the plaster head are completely identical. The difference lies in that the plaster head is an artistic work processed by the artist, while the live drawing of the human head requires artistic modification based on the model's features during the drawing process. Second, their textures, shapes, and sense of form differ greatly. Plaster heads are usually of foreign descent, while human heads are usually of Chinese descent, and there are certain physiological differences in their head features (e.g., hair, eyebrows, nasal bridge, etc.). Candidates should accumulate experience in daily training and establish two sets of different drawing techniques for human heads and plaster heads.
After determining the overall outline and proportions, you can start with the facial features and delve into the structure. Generally, first establish the brow ridge and nasal bridge, then draw the eyes and the tip of the nose, followed by the mouth. When drawing the brow ridge, pay attention to the thickness of the eyebrows and the variations in the expression of the. Male portraits tend to have thicker and coarser eyebrows compared to female portraits, and the bony points of the nasal bridge are more pronounced in male portraits. When drawing the nasal bridge, focus on the rhythmic changes in the modeling of the upper hard bone of the nose, the tip of the nose, the wings of the nose, and the nostrils. When drawing the eyes, pay attention to the model's inner emotions and quickly capture their expression by combining the facial expression. In terms of structural expression, note that the upper eyelid is more prominent than the lower eyelid, positioned between the two eyelids, and should be drawn as a spherical shape. When drawing the mouth, pay attention to the thickness of the upper and lower lips and the curvature of the lip line. The corners of the mouth are the second "window" for expressing emotions, covered by the orbicularis oris muscle.
After clearly expressing the shapes and structures of the facial features, adjust the contours of the hairline, forehead, and chin based on the proportions and positions of the facial features. The facial bony points of male portraits change more significantly than those of female portraits. Finally, depict the relationship between the neck and shoulders and the structure of the clothing. While determining the facial structure and the size and structure of the facial features, correct any errors. Learn to use the principles of symmetry in the left and right bones and muscles of the head, and apply the principles of perspective to check the accuracy of the modeling.