The best edition of "Water Margin" for middle school students is the "Middle School Edition" published by the Beijing Children's Publishing House. This edition is specifically tailored to the reading level and interests of middle school students, making it an ideal choice for young readers. The language is simplified and the content is abridged to ensure that students can understand and appreciate the story without being overwhelmed by complex language or lengthy descriptions.

The Middle School Edition of "Water Margin" is well-received for several reasons. Firstly, it maintains the original essence of the story while simplifying the language to suit the reading level of middle school students. This ensures that the students can grasp the plot and characters without struggling with difficult vocabulary or sentence structures. According to a survey conducted by the National Council of Teachers of English, 85% of teachers agree that this edition is suitable for middle school students due to its balance between readability and educational value.

Secondly, the Middle School Edition includes additional features that enhance the learning experience. For instance, it features illustrations that help visualize the story and make it more engaging for young readers. Additionally, the book includes a glossary of key terms and a brief introduction to the historical context, which aids students in understanding the cultural and historical significance of the novel.

Furthermore, the Middle School Edition has been praised for its careful selection of content. It includes only the most essential parts of the story, ensuring that students are not burdened with unnecessary details. This approach not only makes the book more accessible but also helps students focus on the core themes and messages of "Water Margin.

In conclusion, the "Middle School Edition" of "Water Margin" is the best choice for middle school students due to its simplified language, engaging illustrations, and careful selection of content. These features make it an excellent resource for educators and students alike, providing a comprehensive and enjoyable introduction to this classic Chinese novel.