Here is the honest truth about the "free" part.
: Grammar explanations are often short (2–3 sentences), sometimes making it hard to distinguish between similar points without a teacher. Structured Learning
Since there are no English explanations, you will need a reliable dictionary like Shirabe Jisho to understand the nuances. Use Anki for Active Recall: shin kanzen master n2 grammar pdf extra quality free
The publisher (3A Corporation / Ask Publishing) usually provides the first 20-30 pages of the Shin Kanzen Master series as a free PDF on their official website. While not the full book, this "extra quality" sample is professionally rendered and includes the first two chapters. Search for "Shin Kanzen Master Mastery of Grammar N2 sample download."
The key is consistency rather than intensity. Aim for daily study sessions of 30–90 minutes, depending on your schedule. Here is the honest truth about the "free" part
Many university libraries or Japan Foundation centers carry the series for free borrowing.
To ensure you get an "extra quality" experience, look for a PDF that has these high-quality attributes: sharp, high-contrast text; perfectly aligned pages; and OCR (selectable/searchable text). The ideal version would be a proper PDF/A (archival) version, not just a simple image scan. Use Anki for Active Recall: The publisher (3A
The book organizes grammar points by similarity in meaning or form, helping you learn how to distinguish between nuanced expressions.