Teachers themselves transmit information subconsciously about culture and society through their behaviour and interaction with learners.
Example
Learners read about taboo subjects in British society.
In the classroom
Consideration of sociocultural aspects of language is increasingly important in the context of ELT, which in the past has tended to be UK, or US centred. Project work, tasks outside the class in the target society, webquests and inviting outside speakers into the class allow learners to explore the contexts the target language functions in, and how these contexts affect linguistic choices.
Further links:
https://www.teachingenglish.org.uk/article/sociocultural-awareness-elt
https://www.teachingenglish.org.uk/article/culture-fifth-language-skill
https://www.teachingenglish.org.uk/article/adrian-holliday-intercultural-communication-part-1