From the early days of the discipline researchers have also acknowledged that social aspects play an important role.[54] There have been many different approaches to sociolinguistic study of second-language acquisition, and indeed, according to Rod Ellis, this plurality has meant that "sociolinguistic SLA is replete with a bewildering set of terms referring to the social aspects of L2 acquisition".[55] Common to each of these approaches, however, is a rejection of language as a purely psychological phenomenon; instead, sociolinguistic research views the social context in which language is learned as essential for a proper understanding of the acquisition process.[56]
Ellis identifies three types of social structure which can affect the acquisition of second languages: sociolinguistic setting, specific social factors, and situational factors.[57] Socialinguistic setting refers to the role of the second language in society, such as whether it is spoken by a majority or a minority of the population, whether its use is widespread or restricted to a few functional roles, or whether the society is predominantly bilingual or monolingual.[58] Ellis also includes the distinction of whether the second language is learned in a natural or an educational setting.[59] Specific social factors that can affect second-language acquisition include age, gender, social class, and ethnic identity, with ethnic identity being the one that has received most research attention.[60] Situational factors are those which vary between each social interaction. For example, a learner may use more polite language when talking to someone of higher social status, but more informal language when talking with friends.[61]
There have been several models developed to explain social effects on language acquisition. Schumann's Acculturation Model proposes that learners' rate of development and ultimate level of language achievement is a function of the "social distance" and the "psychological distance" between learners and the second-language community. In Schumann's model the social factors are most important, but the degree to which learners are comfortable with learning the second language also plays a role.[62] Another sociolinguistic model is Gardner's socio-educational model, which was designed to explain classroom language acquisition.[63] The inter-group model proposes "ethnolinguistic vitality" as a key construct for second-language acquisition.[64] Language socialization is an approach with the premise that "linguistic and cultural knowledge are constructed through each other",[65] and saw increased attention after the year 2000.[66] Finally, Norton's theory of social identity is an attempt to codify the relationship between power, identity, and language acquisition.[67]