What is the meaning of "work-brush"?

Working brush painting, also known as "fine brush painting", is one of the categories of Chinese painting techniques, with a rigorous and delicate brushwork to depict the scene of Chinese painting expression, as opposed to the writing of the painting. Work-brush painting belongs to the category of neat and detailed painting methods, such as Song Dynasty courtyard painting, Ming Dynasty Qiu Ying figure painting, etc.; work-brush painting requires that "there is a clever, dense and fine" (Northern Song Dynasty Han Clumsy, "Shanshui Pure Collection"), ink and watercolor, light-red, green and blue, gold and blue, and boundary paintings and other forms of art can be expressed in work-brush paintings. The painting has a long history, originating in the Warring States period and flourishing in the Tang Dynasty; after the end of the Ming Dynasty, with the introduction of Western painting techniques to China, Chinese and Western paintings borrowed from each other, making the creation of the painting more accurate in its modeling. Work-brush painting has developed y along the trajectory of integrating literature, calligraphy, philosophy and poetic language, absorbing elements of new visual art languages from the East and the West, expanding new fields of materials and techniques, and incorporating the outlining and rendering of traditional work-brush painting, the decorative nature of graphic expression, as well as the Western realist approach and dreamlike mood into contemporary work-brush painting.