The trademarks of merchants printed on school uniforms must be analyzed in detail:

1. If the use permission of the registered trademark owner is obtained, it is not illegal; if permission is not obtained in advance, it will be illegal afterwards. If the right holder's consent cannot be obtained, this constitutes infringement of the exclusive right to use a registered trademark.

2. If the merchant’s trademark is not registered but is a well-known trademark in China, the usage regulations are the same as the first point.

3. The merchant’s trademark is not a registered trademark, nor is it a registered trademark in China. The printing behavior is generally not considered an infringement.

Finally, since it is a school uniform, the merchant’s trademark printed on it feels like a commercial advertisement and feels inappropriate.