Do I need to trace the black characters on the Huaxia Wanjuan copybook? Why is the whole side sometimes black, instead of red? What is the use of that layer of paper on top?

As a calligraphy practitioner, I am the most qualified to answer this, because I personally like to practice calligraphy. Whether it is a hard pen or a soft pen, I like it. Let me tell you about this. In the Huaxia Wanjuan copybook, the black characters are drawn, which is called drawing red. You can also use the other side to draw red. This is to give you an impression of the structure of the font. It is specially designed like this. You need to use your carbon pen or You can use either a pen or a pencil, and then copy the lettering above, then trace and copy. In fact, this curtain method is not good. You might as well find a copybook to copy, that is to say, you follow the copybook. Imitation, no writing on the practice paper, so that you can master it quickly, and this kind of red tracing effect is better