Calligraphy is divided into brush calligraphy and hard-pen calligraphy.
If it is brush calligraphy, the signature usually adopts the traditional format. There can be upper and lower signatures. The only common one is the following paragraph, in the format:
Time (generally not using the Gregorian calendar) (Place) Author (Respect) Letter. For example: "The spring moon of Guimao is written in honor of XX in Gufeng Hall".
In traditional calligraphy signatures, the date is calculated according to the stems and branches, the month is calculated according to the lunar calendar, and the nickname is written, which is generally not specific to a certain day. If it is hard-pen calligraphy and horizontal writing, it can be in modern format: XXX calligraphy on X month X day 2023. If it is vertically arranged, it should also follow the traditional format.