The method is:

When you want to enter a person's name in a black box, press the "Ctrl+F9" key combination, and a curly brace with a gray background will appear (note: you must enter curly braces with this key combination), and a vertical cursor will flash inside. Then you switch to the English input method state, enter eq, leave a blank, and then enter \ x and the left bracket (enter the name at this time, and then enter the right bracket in the English state), and enter all of them.

For example, if you want to add a box to "person's name", just enter "eq\x (person's name)" in the curly braces at the bottom of the gray, and then switch the domain code. The function of the shopping mall is very powerful. You can add lines to the top, bottom, left and right of words, enter mathematical formulas, determinants and so on. If you are interested, you can learn.