The book allows you to learn at a good pace, using a fair amount of repetition through exercises and a quiz at the end of each lesson. The vocabulary is relevant, and the reader is expected to learn it at a reasonable rate, unlike some other books. Although, if you want to be able to speak fluently volume one will not be enough. The only reason I gave the book four stars instead of five is that it is almost all in the polite form of the language. There is little of the casual form used when speaking with non-business friends. However, this is by no means a crucial fallback, since the differences are by no means great. Assuming the reader is dedicated, this book acts as an excellent tool both for vocabulary and for grammar. Gambatte!