are cyan magenta and yellow belong to three primary colors used in printing

Yes, in the context of printing and specifically the design industry, Cyan, Magenta, and Yellow are considered the three primary colors. These colors, along with Black for shadow and contrast (often denoted as CMYK, where "K" stands for Key or Black), are used to represent full-color images. Below is the information in Chinese: 是的，在印刷和设计行业中，青色（Cyan）、品红色（Magenta）和黄色（Yellow）被视为三原色。连同用于阴影和对比的黑色（经常表示为CMYK，“K”代表关键或黑色一起），这些颜色用来再现全彩图像。