The stroke is called apostrophe, which is one of the basic strokes of Chinese characters.
In brush calligraphy, the quality of writing also determines the mastery of brush calligraphy. The "Modern Chinese Common Character List" stipulates five categories of basic strokes: horizontal, vertical, apostrophe, dot, and fold.
The writing characters include: people, Yang, 伧, 伥, Chuan, cutting, imitation, husband, Fu, Huo, Ji, price, piece, couple, Lun, 仳, Ren, injury, like, Wa, Wei, pseudo, Wu, Wu, 伈, Xiu, 伢, Yi, You, 伛, Zhong, 伯, Chao, Hua, Shang, Wu, Chun, Bo, Ban, Ge, Guan, Qin, Lao, Low, Paper, generation, residence, Ren, pseudo, instrument, you, it, some, draw, refer to, generation, pay, 仡, people, 仫, 千,仞, 三, official, he, immortal, instrument, berth, battle, Chaos, or, you, lost, Qi, body, theory, Hua, Qiu, Ding, only, D, servant, benevolence, still, even, D.