second language

A second language (L2) is any language learned after the first language or mother tongue (L1). Some languages, often called auxiliary languages, are used primarily as second languages or lingua francas. It is quite possible that the first language a person learns may no longer be their dominant language, that is, the one he or she uses most or the one with which he or she is most comfortable in. For example, the Canadian census defines first language for its purposes as "the first language learned in childhood and still spoken", recognizing that for some, the earliest language may be lost, a process known as language attrition. This can happen when young children move, with or without their family (because of immigration or international adoption), to a new language environment.
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