Change of words

Recently in Japan, many adults claim that the number of young people, who use bad and wrong words and grammers, is increasing, and they should speak "right" Japanese. However, it's very difficult to define "right", because it's common that words or useage of words change, if time change. So, it's very natural that young people talk a bit differently from adults do. Young people have the rights they talk as they want in some degrees, though it's better to use good and polite words. In short, Japanese young people should be careful in their choice of words according to circumstances.