With the economic development and social progress,great changes have taken place in modern Japan,a reflection of which is the continuous appearance of popular slangs.Some of the slangs are used widely,some of them are used daily and some others have been written into dictionaries as fixed expressions.As a result of being flexible in forms and popular among young people,slang has caused Japanese to change with regard to its regular word meaning,its grammar as well as its structure.This paper analyzes the dev...