The first language of a child is part of that child's personal, social and cultural identity.[3] Another impact of the first language is that it brings about the reflection and learning of successful social patterns of acting and speaking.[clarification needed][4] It is basically responsible for differentiating the linguistic competence of acting.[clarification needed] While some argue that there is no such thing as a "native speaker" or a "mother tongue", it is important[in what context?] to understand the key terms as well as to understand what it means to be a "non-native" speaker, and the implications that can have on one's life. Research suggests that while a non-native speaker may develop fluency in a targeted language after about two years of immersion, it can take between five and seven years for that child to be on the same working level as their native speaking counterparts [citation needed].