In traditional second language teaching, teachers teach the second language as a subject. Thus, their teaching focus is more on linguistic features rather than communicative competence. Since the 1960s, sociolinguistics, as a new field, reveals that language has a close connection with social activities rather than a pure linguistic subject. Then, a series of researchers (Hornberger & McKay, 2010; Geeslin & Long, 2014) confirm the necessity of learning the language in the social context. This study will demonstrate that social factors, such as ethnicity, gender, and social class, which bring variants in linguistic forms, style, and register, are relevant closely to language teaching. Through concerning these sociolinguistic variants, educators would realize the importance of teaching the second language in the social context. Finally, this paper will list three current issues in a traditional class: interaction neglection, overemphasized standard accents, and silence phenomena. After reviewing the inspirations gained from sociolinguistic variation, this study will raise several suggestions to promote language teaching changes in terms of contents and methods.