P.S. is the abbreviation of Post Scripts, which is interpreted as postscript and postscript. This is a common way to supplement information in early English letters. The reason is clear: handwritten letters will not look good if they are changed again, and then they will become a way to express important information. Today's e-mail also uses this method to remind the recipient that this is important information. In addition, there are appendices, postscript and addendum; Conclusion (after news broadcast); The abbreviation of Photoshop (image processing software).
Because this way is rarely used in formal articles, there are no special rules for the expression of P.S., usually: P.S., PS:, P.S., PS. , PS .ing.com one-stop study abroad strategy