When the calligraphy teacher writes, the pen always draws back and forth, and nothing can be written. Is this major?

I don't know what you mean by sketching back and forth Sometimes, some strokes need to change the direction of the pen for the effect, but sketching back and forth or repeatedly tracing is very amateur, which is not only not conducive to the improvement of his own calligraphy level, but also a wrong demonstration for students.

I guess you are also a calligraphy lover. In fact, in addition to learning from professional calligraphy teachers, writing tools are also very important, such as writing brushes. If you want to know which brushes are easy to write, you can find this article to read "Top Ten Brush Brands in China (with Selection and Maintenance Methods of Brush)". I hope it will help you ~ I wish you progress!