Here is a breakdown of the two books
Shin Nihongo no Kiso I
100 hours study time, 25 lessons, 800 vocab items, and 75 sentence patterns
Shin Nihongo no Kiso II
100 hours study time, 25 lessons, 680 vocab items, and 64 sentence patterns
The series starts with the Shin Nihongo no Kiso Main Textbook with seperate English Translation and Grammatical notes available. The main textbook is all in Japanese, which is a great way to immerse yourself in the language, but I highly recommend getting English Translation and Grammatical notes as they really helped me. The English Translation lists the vocabulary for each chapter in romaji, kana and English as well as an English translation of the sentence patterns and example sentences from each chapter. The Grammatical Notes in English explain in detail the grammatical points and structures for each chapter with lots of examples to help you with correct usage.
I have found that my grammar, vocabulary, sentence structure and reading and writing improved dramatically using this book. It was also a great aid in studying for the Japanese Language Proficiency Test.
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