Look at the thickness: the paper thickness of the eighth edition of the genuine Oxford Advanced English-Chinese Learning Dictionary is relatively thin, and it will be even heavier if it is thousands of pages thick. The original version is about 69mm, and the pirated version is about 74 mm.

Reading Ridge: Genuine products are almost straight, while pirated products are obviously radian.

Look at the stains: pirated printing is general, although it does not affect the recognition, but there are many stains on the paper.

Look at the font color: the eighth edition of the pirated Oxford Advanced English-Chinese Learning Dictionary has a different font color. It will look much more comfortable if it is genuine.

Look at the clarity: it is mainly printed clearly, and piracy is not as good as genuine.

Look at the watermark: The second page of the original is the same as RMB, made of watermark paper, with a reflection on the side, showing the watermark of the book, while the pirated eighth edition of Oxford Advanced Learner's English-Chinese Dictionary does not.