A book explaining the importance of the language environment for nurturing children's brains. - Title: The Thirty Million Word Gap - Author: Dana Suskind - Translators: Itsumi Kakeshita, Shizuko Takayama - Price: 1800 yen Thank you for looking. There is a small scratch on the cover, but otherwise it is generally clean. The inside of the book is very clean with no writing or markings.