1 means to make full use of the upper end and not use the lower end. This format should be two words per line, written from right to left.
2, that is, write fewer numbers, and use the width of the sector to write two or four words horizontally from right to left to measure.
3. The upper end is written in turn, and the lower end is staggered. The inscriptions should be wonderful and form a pattern of scattered lengths.