The author has limited this book to modern colloquial Japanese, and does not overburden the student with literary language, rarely used alternate forms, unnecessary abrupt form, causative and direct conditionals, and similar forms that might be required for a knowledge of the written language. On the other hand, this book is not simplified Japanese, nor baby Japanese, nor kitchen Japanese. It is a full idiomatic language, with thorough treatments of the material you really need: the noun, pronoun, adjective, demonstrative words, adverb, negative forms, Chinese forms, courtesy and honorific forms, idiomatic constructions, word order, relationship of ideas, syntax, etc.