See if there is a bar code and pricing on the back cover. If there is no barcode, it must be a pirated book.

The way to identify pirated books: first look at the cover, which can be observed from the aspects of color, clarity, cover paper quality, book binding and so on. Specifically, pirated books generally have bright cover colors and muddy handwriting. The cover paper is thin and the offset glue overflows. Hardcover books may lack a plug cloth (plug cloth: silk cotton strip cloth with a tightly woven ridge at one end). Stick it on both ends of the spine to protect the spine incision and increase the aesthetic feeling of the book. ) or without front and rear ring linings. Second, see if there is a barcode and pricing on the back cover. If there is no barcode, it must be a pirated book. Third, you can also look at the copyright page, usually on the back of the title page or at the end of the text, with CIP data printed on it. It is relatively simple to check whether the ISBN of the copyright page is consistent with the barcode on the back cover, and the inconsistency is generally piracy.