You can practice calligraphy with an art pen, which is actually a calligraphy pen. Its writing effect is unmatched by ordinary pens, and it will not violate the spirit of calligraphy. Even if you write in the sand with a wooden stick, you can write calligraphy. Don't worry about this. Of course, there is one problem. Being used to writing ordinary pens with fine art pens may be somewhat uncomfortable, so it is better to use ordinary pens in general practice. After all, practicing calligraphy is for daily use, and it is more likely to use ordinary pens every day.