Do I have to write all 50 squares of hard pen calligraphy?

You don't have to write all 50 squares of hard pen calligraphy. There is no hard and fast rule for hard pen 50-grid calligraphy. When practicing hard-pen calligraphy with hard-pen calligraphy paper, for the purpose of saving, try to fill it up, that is, write out all the grids. Hard-pen calligraphy works should be typeset according to the content and composition, and whether to leave blank should be decided according to the content. If a single word needs to fill a grid, it is not necessary to fill the grid on the hard pen calligraphy paper when writing with hard pen, so as to occupy two-thirds of the grid.